Online Tools Collection
374 tools · all free · no sign-up, use instantly
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MD5 Online Decrypt
This MD5 online decryption tool quickly recovers MD5 hashes through reverse lookup. Enter a 32-character ciphertext and get the original text with one click — ideal for cryptography research and information security assessment.
Encoding & Encryption 308.7k uses
Run Python Online
Run Python code online with support for installing a rich set of third-party libraries. It includes built-in chart rendering, virtual file management, preview and download, and works instantly in a browser sandbox.
Development 288.4k uses
IP Address Lookup
A professional online IP address lookup tool offering fast, accurate global IP geolocation. It precisely shows the country, province, city and network provider associated with an IP.
Webmaster Tools 230.2k uses
Random Phone Number Generator
A free online random phone number generator supporting many countries and regions. Generate virtual numbers in realistic formats in bulk and export the results to Excel or TXT.
Office & Study 192.5k uses
Online Calculator
A free online calculator that works instantly in your browser with no installation. Basic mode supports add, subtract, multiply, divide, percentages and sign toggling, while scientific mode adds trigonometry, logarithms, roots, powers, factorials, absolute value and degree/radian switching, with one-click result copying.
Everyday Life 125k uses
BMI Calculator
A free online BMI calculator: enter your height and weight to instantly get your body mass index. See whether you are underweight, normal, overweight or obese, plus tailored diet and exercise tips to help you manage your weight scientifically.
Everyday Life 83k uses
Timestamp Converter
An online Unix timestamp converter that shows the current timestamp in real time and converts between timestamps and dates in both directions. Switch between seconds and milliseconds precision and pick your time zone — a must-have for development and debugging.
Webmaster Tools 52k uses
Online Unit Converter
A free online unit converter covering length, weight, area, volume, temperature, data size, time, speed and more. Get instant results as you type, swap units, and copy with one click on any phone or computer.
Everyday Life 46k uses
Special Symbols Collection
A comprehensive and efficient online special symbols collection featuring emojis, math symbols, arrows, currency signs, punctuation, numbered lists and thousands more characters. Search by keyword and copy any symbol with a single click to boost your work and social efficiency.
Everyday Life 38k uses
Resume Builder
Build a clean, professional resume in your browser with live preview. Fill in your details, experience, education and skills, then export or print as PDF.
Office & Study 17 uses
Page Speed Checker
Measure a page’s response status, total load time, content size, server and content type, count scripts, styles, images and iframes, and get a 0–100 performance score with suggestions.
Webmaster Tools 13 uses
Text to Speech
Convert text into natural speech in your browser. Choose a voice and language, fine-tune rate, pitch and volume, then play or pause it aloud instantly.
Audio Processing 12 uses
Everyday Life 8
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Online Calculator
A free online calculator that works instantly in your browser with no installation. Basic mode supports add, subtract, multiply, divide, percentages and sign toggling, while scientific mode adds trigonometry, logarithms, roots, powers, factorials, absolute value and degree/radian switching, with one-click result copying.
Everyday Life 125k uses
QQ Avatar Lookup
Fetch QQ avatars, QQ Mail avatars and QQ Zone avatars online. Simply enter a QQ number to instantly display the matching avatar — no login required and available on any device.
Everyday Life 114.9k uses
Online Emoji Collection
The latest and most complete online Emoji collection, featuring thousands of common and up-to-date emojis. Browse by category or search by keyword, then copy and paste with one click.
Everyday Life 108.5k uses
BMI Calculator
A free online BMI calculator: enter your height and weight to instantly get your body mass index. See whether you are underweight, normal, overweight or obese, plus tailored diet and exercise tips to help you manage your weight scientifically.
Everyday Life 83k uses
Online Unit Converter
A free online unit converter covering length, weight, area, volume, temperature, data size, time, speed and more. Get instant results as you type, swap units, and copy with one click on any phone or computer.
Everyday Life 46k uses
Income Tax Calculator
A free online income tax calculator that computes personal income tax on wages and salaries using the cumulative withholding method. It supports social insurance and housing fund deductions as well as special additional deductions, and shows your after-tax salary.
Everyday Life 44k uses
Special Symbols Collection
A comprehensive and efficient online special symbols collection featuring emojis, math symbols, arrows, currency signs, punctuation, numbered lists and thousands more characters. Search by keyword and copy any symbol with a single click to boost your work and social efficiency.
Everyday Life 38k uses
Age & Birthday Calculator
A free online age calculator: enter your birth date to get your exact age in years, days lived and months, plus your zodiac sign, Chinese zodiac and the days until your next birthday.
Everyday Life 31k uses
Webmaster Tools 8
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IP Address Lookup
A professional online IP address lookup tool offering fast, accurate global IP geolocation. It precisely shows the country, province, city and network provider associated with an IP.
Webmaster Tools 230.2k uses
Domain Whois Lookup
A free online Whois lookup tool supporting a large number of top-level domains. Quickly get the domain registrar, registration date, expiry date, DNS servers and registrant information.
Webmaster Tools 86.7k uses
Network Port Reference
A free online network port reference listing the services and protocols of common and registered ports. Search by port number or keyword, perfect for development, operations and security troubleshooting.
Webmaster Tools 66.1k uses
Batch Whois Lookup
A free online batch Whois lookup tool that accepts multiple domains at once and lists each domain's registration status, registrar, registration and expiry dates line by line. It automatically distinguishes registered, unregistered, registry-reserved and unsupported domains, and results can be copied or exported to CSV.
Webmaster Tools 54k uses
Timestamp Converter
An online Unix timestamp converter that shows the current timestamp in real time and converts between timestamps and dates in both directions. Switch between seconds and milliseconds precision and pick your time zone — a must-have for development and debugging.
Webmaster Tools 52k uses
UTM Link Builder
An online UTM link builder: fill in the site URL and parameters such as utm_source, utm_medium and utm_campaign to generate a trackable campaign link — a must-have for marketing and traffic analysis.
Webmaster Tools 16k uses
DNS Lookup
A free online DNS lookup tool supporting A, AAAA, CNAME, MX, TXT, NS, SOA and CAA records. Enter a domain to instantly get its resolution results and quickly troubleshoot domain, email and website configuration issues.
Webmaster Tools 16 uses
SSL Certificate Checker
A free online SSL certificate checker: enter a domain to view the certificate issuer, validity period, remaining days and supported protocols, and quickly tell whether an HTTPS certificate is valid or about to expire.
Webmaster Tools 13 uses
Development 8
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Run Python Online
Run Python code online with support for installing a rich set of third-party libraries. It includes built-in chart rendering, virtual file management, preview and download, and works instantly in a browser sandbox.
Development 288.4k uses
JSON Formatter & Validator
A free online JSON formatter and validator: beautify, minify and syntax-check JSON with one click. Choose 2/4-space or tab indentation and get error position hints — a handy tool for API debugging and data cleanup.
Development 36k uses
URL Encode / Decode
An online URL encoder and decoder that supports both whole-URL and single-parameter modes. Escape or restore Chinese text and special characters with one click — essential for development and API integration.
Development 29k uses
Regex Tester
An online regular expression tester with real-time match highlighting, group capture, and flags such as case-insensitive and global. See matches and their count instantly — essential for developing and debugging regex.
Development 24k uses
UUID Generator
A free online UUID generator that creates version 4 (random) universally unique identifiers in bulk. Options include uppercase, removing hyphens and up to 100 IDs at once — a must-have for development and testing.
Development 21k uses
Cron Expression Parser
An online Cron expression parser supporting both the standard 5-field and the 6-field (with seconds) formats. It validates the expression and computes the next several run times — a must-have for operations and scheduled-task debugging.
Development 20k uses
URL Parser
An online URL parser that breaks a web address into protocol, host, port, path, query parameters and anchor, and lists every parameter clearly in a table — essential for development and API debugging.
Development 18k uses
JWT Decoder
An online JWT decoder: paste a JSON Web Token to decode its Header, Payload and Signature, and automatically detect issue and expiry times. Everything is parsed locally without uploading, keeping it safe and fast.
Development 17k uses
Encoding & Encryption 8
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MD5 Online Decrypt
This MD5 online decryption tool quickly recovers MD5 hashes through reverse lookup. Enter a 32-character ciphertext and get the original text with one click — ideal for cryptography research and information security assessment.
Encoding & Encryption 308.7k uses
Random Password Generator
An online random password generator that lets you customize length and character sets to create strong random passwords. Generate in bulk and copy with one click to strengthen your account security.
Encoding & Encryption 61k uses
Base64 Encode & Decode
An online Base64 encoding and decoding tool that handles Chinese text and file content. Encode or restore with one click — a common utility for development and debugging.
Encoding & Encryption 41k uses
Hash Generator
A free online hash generator supporting MD5, SHA-1, SHA-256, SHA-384 and SHA-512. Enter text to compute a digest instantly, switch between upper and lower case, and copy with one click — a common utility for development and data verification.
Encoding & Encryption 26k uses
HTML Entity Encoder
An online HTML entity encoder and decoder: escape special characters such as angle brackets and ampersands into HTML entities, or restore them with one click. It handles Chinese text and bulk input — a common tool for front-end and web development.
Encoding & Encryption 19k uses
TOTP Code Generator
An online TOTP code generator following the RFC 6238 standard. Enter a Base32 secret to generate 6-digit codes identical to Google and Microsoft Authenticator and see the remaining validity time, ideal for two-factor authentication debugging.
Encoding & Encryption 13 uses
AES Encrypt & Decrypt
An online AES symmetric encryption tool supporting AES-CBC and AES-GCM modes with 128/192/256-bit keys. Customize the key and IV; everything is computed locally in your browser and never uploaded, making it safe and efficient.
Encoding & Encryption 12 uses
HMAC Generator
An online HMAC calculator supporting five algorithms — HMAC-MD5, SHA1, SHA256, SHA384 and SHA512. Enter the text and key to generate a hexadecimal or Base64 signature, a must-have for API signature verification and data integrity checks.
Encoding & Encryption 12 uses
Office & Study 8
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Random Phone Number Generator
A free online random phone number generator supporting many countries and regions. Generate virtual numbers in realistic formats in bulk and export the results to Excel or TXT.
Office & Study 192.5k uses
Online Word Count
An online word count tool that shows characters, words, Chinese characters, lines, paragraphs and sentences in real time, and estimates reading time. A must-have before writing copy or checking a thesis.
Office & Study 25k uses
Text Diff Tool
A free online text diff tool that compares two texts line by line and highlights additions and deletions. It supports ignoring case and leading/trailing whitespace, ideal for version proofreading and copy revision.
Office & Study 18k uses
Text Case Converter
An online text case converter that switches between UPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case and kebab-case with one click. A handy tool for writing and programming.
Office & Study 14k uses
Lorem Ipsum Generator
A free online Lorem Ipsum placeholder text generator. Customize the number of paragraphs and sentences per paragraph, generate dummy text for layout mockups in one click, and copy or clear it easily — ideal for design and front-end work.
Office & Study 13k uses
Resume Builder
Build a clean, professional resume in your browser with live preview. Fill in your details, experience, education and skills, then export or print as PDF.
Office & Study 17 uses
Simple Expense Tracker
A free online expense tracker: record income and expenses by date, get an automatic balance and organise entries by category with notes. Data is stored locally in your browser — a handy tool for daily bookkeeping and budgeting.
Office & Study 13 uses
Date Calculator
A free online date calculator: find the number of days between two dates, or add and subtract days, weeks, months or years from a given date and see the resulting weekday. Ideal for scheduling and anniversary planning.
Office & Study 12 uses
Fun & Leisure 8
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QQ Number Value Evaluator
An intelligent QQ number valuation tool that analyzes number length, digit patterns, rarity and special meanings to provide market value analysis and price references.
Fun & Leisure 97k uses
Random Number Generator
An online random number generator that produces random integers within a range and count you specify. It supports unique values and sorting, perfect for lucky draws, roll calls and test data.
Fun & Leisure 27k uses
Morse Code Converter
An online Morse code converter that translates between text and Morse code in both directions, covering letters, digits and common punctuation. Encode or decode with one click and copy the result — great for fun learning and signal enthusiasts.
Fun & Leisure 12k uses
Reaction Time Test
Online reaction speed test: click as soon as the screen turns green to measure your reaction time in milliseconds, with multiple results and an average—handy for fun tests and reaction training.
Fun & Leisure 16 uses
Lucky Draw Wheel
An online lucky draw wheel: customize the options, generate a colorful spinning wheel and click to draw a random result. Great for making decisions, picking names and event raffles — simple and fun.
Fun & Leisure 15 uses
Typing Speed Test
An online typing speed test with random English and Chinese texts that tracks your speed, accuracy and time in real time — handy for practice and assessment.
Fun & Leisure 15 uses
Love Calculator
A fun online love calculator: enter two names and a playful deterministic algorithm instantly computes a 0–100 love score for the pair, with a progress bar and a matching comment from "perfect match" to "hardly a match". The result is for entertainment only—great for chatting and games with friends.
Fun & Leisure 14 uses
Dice Roller, Coin Flip & Rock-Paper-Scissors
Online dice roller, coin flip and rock-paper-scissors tool. A single click gives you a random result with animation—great for making decisions and having fun.
Fun & Leisure 13 uses
Image Processing 8
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QR Code Generator
A free online QR code generator: enter text or a URL to create a QR code image. Adjust the size and error correction level, then download and save it.
Image Processing 58k uses
Color Converter
An online color converter that converts between HEX, RGB and HSL in real time, with a built-in color picker and common palette. What you see is what you get — essential for front-end theming and design color picking.
Image Processing 22k uses
Image to Base64
An online image to Base64 tool: drag and drop or select an image to convert it to a Data URL instantly in your browser. Copy it or download as text — your image is never uploaded, keeping it safe and fast.
Image Processing 16k uses
Image Compressor
A free online image compression tool supporting JPG, PNG and WebP with adjustable quality. Everything is processed locally in your browser without uploading, quickly reducing image size while keeping it as clear as possible.
Image Processing 15k uses
CSS Gradient Generator
An online CSS gradient generator: visually adjust the gradient type, angle and colors, preview the result in real time, and copy the CSS code with one click — a great helper for front-end theming and background design.
Image Processing 11k uses
Image to SVG
Convert a bitmap image into a scalable SVG in your browser by tracing it into vector paths. Adjust the edge threshold and number of colors. Processed locally, never uploaded.
Image Processing 14 uses
SVG to PNG
Render an SVG into a PNG at a chosen size or scale in your browser. Supports transparent backgrounds and exporting multiple resolutions. Processed locally.
Image Processing 13 uses
Image Slicer
Slice one large image into a grid of smaller images in your browser and download them as a ZIP. Great for sprite sheets and 3x3 grid covers. Processed locally.
Image Processing 12 uses
Audio Processing 8
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Audio Size Compressor
A free, professional online audio compressor supporting many input formats with both lossy compression and lossless conversion modes. Customize bitrate, sample rate and channels, all processed locally in your browser to protect your privacy.
Audio Processing 84.8k uses
Audio Joiner
Join several audio files into one in your browser. Add two or more tracks, reorder them with up/down controls, then merge them in sequence and export a single WAV — all processed locally without uploading.
Audio Processing 12 uses
Audio Speed & Pitch Changer
Change the speed and pitch of any audio in your browser. Adjust playback speed and transpose the pitch in semitones independently, preview the result, then export it as a WAV — all processed locally without uploading.
Audio Processing 12 uses
Audio Waveform Generator
Free online audio waveform generator: turn any MP3, WAV or OGG file into a clear waveform image with adjustable zoom and colors, then export it as a PNG. Processed locally, never uploaded.
Audio Processing 12 uses
Audio BPM Detector
Free online audio BPM detector: estimate a track’s tempo in beats per minute for music production and editing. Runs fully in your browser — processed locally, never uploaded.
Audio Processing 12 uses
Audio Silence Cutter
Free online audio silence cutter: automatically detect and remove silent parts to shorten a recording, with adjustable threshold and minimum length. Export as WAV — processed locally, never uploaded.
Audio Processing 12 uses
Audio Mixer & Merger
Free online audio mixer: add multiple audio files, adjust each track’s volume, and mix them into one combined track, export as WAV. Everything is processed locally in your browser and never uploaded.
Audio Processing 12 uses
Audio Format Converter
Convert audio files between popular formats right in your browser. Re-encode to WAV or MP3, choose bitrate and channels, then download — no upload required.
Audio Processing 12 uses
Video Processing 8
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Subtitle Merger & Splitter
Merge several subtitle files into one, or split a long subtitle into multiple files by time or by cue count. Cues are reindexed automatically and everything is processed locally without uploading.
Video Processing 13 uses
Video Watermark
Add a text or image watermark to any video right in your browser. Choose the position, size, opacity and colour, then export a watermarked WebM file — fully local, with nothing uploaded.
Video Processing 13 uses
Video Frame Extractor
Grab clean still frames from any video right in your browser. Choose interval, fixed count or custom timestamps, then export as PNG or JPG — no upload and no software.
Video Processing 13 uses
SRT Subtitle Editor
Edit SRT subtitles visually in your browser: adjust each cue's timeline and text, preview the result, change durations and fine-tune in bulk. Everything runs locally, nothing is uploaded.
Video Processing 12 uses
Subtitle Format Converter
Convert subtitle files between SRT, WebVTT and ASS formats while keeping the timeline and basic styling. A fast, free online converter that runs entirely in your browser, so nothing is ever uploaded.
Video Processing 12 uses
Subtitle Time Shifter
Shift subtitle timing forward or backward, or scale it proportionally, to fix audio that is out of sync. Supports positive and negative offsets and runs fully locally in your browser, with no upload.
Video Processing 12 uses
Subtitle Text Cleaner
Clean subtitle text in bulk: remove ad lines, blank lines and duplicates, and unify punctuation and letter case. Ideal for tidying up SRT, VTT or ASS files locally in your browser, with no upload.
Video Processing 12 uses
Video Merger
Merge multiple videos into one by joining them in any order. Reorder the clips, then combine and export a single WebM file directly in your browser — no upload, no server, no watermark.
Video Processing 12 uses
Charts & Data Viz 6
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Line Chart Generator
Turn plain numbers into polished line charts right in your browser. Add one or more series, customize the title, palette, grid and smooth curves, then export as crisp SVG or high-resolution PNG — no upload, no sign-up.
Charts & Data Viz 11 uses
Bar Chart Generator
Create clean bar charts and grouped bar charts from plain text right in your browser. Switch between vertical and horizontal bars, tweak colors, value labels and grid, then download as crisp SVG or high-resolution PNG — nothing is uploaded.
Charts & Data Viz 11 uses
Pie Chart Generator
Turn simple lists into attractive pie and donut charts right in your browser. Adjust colors, legend position and percentage labels, set the inner radius, then export as crisp SVG or high-resolution PNG — fully private, no upload.
Charts & Data Viz 11 uses
Radar Chart Generator
Turn your data into a clean radar chart right in the browser. Enter one axis per line, adjust grid levels, palette and multiple series, then export as SVG or PNG — no upload required.
Charts & Data Viz 11 uses
CSV to Chart
Paste CSV data or load a file and instantly get a line, bar or pie chart. Pick the label and value columns, toggle legend, values and grid, and download as SVG or PNG — all client-side, nothing uploaded.
Charts & Data Viz 11 uses
Sparkline Generator
Create compact sparklines from a list of numbers in seconds. Fine-tune area fill, last-point and min/max markers, line width, color and size, then copy the inline SVG or download as SVG or PNG — no upload.
Charts & Data Viz 11 uses
AI 8
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Embedding Cost Calculator
Estimate the cost of embedding calls from document count, average length and model price. Includes built-in prices for popular models and knowledge-base scale projections.
AI 14 uses
Stable Diffusion Prompt Builder
Build Stable Diffusion and Midjourney prompts visually: pick tags for subject, style, lens, lighting, quality and negative prompts, add your own tags, set weights like (word:1.2), and copy the finished positive and negative prompts in real time.
AI 11 uses
Text Summarizer
Extractive text summarizer that runs entirely in your browser. It scores sentences by word frequency and position to pull out the key points and produce a Chinese or English summary — great for skimming long texts.
AI 11 uses
Keyword Extractor
Extract high-frequency and topic keywords from any text using word frequency and TF-IDF, all locally in your browser. Works with Chinese and English — handy for SEO and content analysis.
AI 11 uses
System Prompt Library
A curated library of system prompt templates for writing, coding, translation, customer support and more. Copy in one click or edit before use.
AI 11 uses
Markdown to Prompt
Turn a Markdown document into a clean, well-structured prompt. Heading levels, lists and code blocks are preserved, and you can prepend or append instructions before copying.
AI 11 uses
AI Chat Export
Export AI conversations as clean Markdown or styled HTML. Supports role labels and keeps code blocks intact — perfect for archiving or sharing.
AI 11 uses
AI Token Counter
Free online AI token counter: paste any text to instantly estimate the input token count for GPT, Claude, Gemini and other LLMs. Handles mixed Chinese/English content and shows characters, words, estimated tokens and per-model cost — ideal for prompt debugging and cost estimation.
AI 11 uses
Education & Science 7
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Probability & Combinatorics Calculator
Calculate permutations A(n,k), combinations C(n,k) and factorials online, plus binomial probabilities. Exact big-integer results and formulas are shown, computed locally in your browser.
Education & Science 12 uses
Scientific Notation Converter
Convert between decimal numbers and scientific notation online, in both directions, with optional significant digits and engineering notation. Large numbers use string math, fully local.
Education & Science 12 uses
Quadratic Equation Solver
Solve quadratic equations online. Enter coefficients a, b and c to get the discriminant, the real or complex roots and the full solution steps. Runs locally in your browser, nothing is uploaded.
Education & Science 11 uses
Molar Mass Calculator
Calculate the molar mass of any chemical formula online. Parse elements, parentheses and hydrates to get the total molar mass and the elemental mass fractions. Runs locally in your browser.
Education & Science 11 uses
Periodic Table of Elements
Browse the periodic table of all 118 elements online. View atomic number, symbol, name, relative atomic mass and category, with instant search and category filters. Runs locally.
Education & Science 11 uses
Significant Figures Calculator
Identify the number of significant figures in a value and round it to any number of sig figs online. Ideal for lab data and science homework, computed locally in your browser.
Education & Science 11 uses
Physics Formula Calculator
Solve common physics formulas online: speed, acceleration, force, work, power, Ohm's law, density and kinetic energy. Enter the known values, leave the unknown blank. Runs locally.
Education & Science 11 uses
Chinese Text 8
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Chinese Address Parser
Parse a Chinese address online into province, city, district and street. Built-in 34 province-level regions and common suffix rules. Runs locally in your browser.
Chinese Text 12 uses
Chinese to Pinyin Converter
Convert Chinese characters into pinyin right in your browser, with tone marks, numbered tones or none, plus full pinyin, initials and finals modes. Runs locally, never uploaded.
Chinese Text 11 uses
Chinese to Pinyin Slug
Turn a Chinese title into a clean, URL-friendly pinyin slug in your browser. Choose the separator, convert to lowercase and get a ready-to-use link. Runs locally, never uploaded.
Chinese Text 11 uses
Chinese Numeral Converter
Convert between Arabic digits and Chinese numerals in your browser. Choose lowercase or formal uppercase amounts and an optional ordinal form like 第. Everything is processed locally, never uploaded.
Chinese Text 11 uses
Chinese Word Segmentation
Split a Chinese sentence into words in your browser using a built-in dictionary and forward maximum matching. Pick a word separator and copy the result. Works offline, never uploaded.
Chinese Text 11 uses
Chinese Word Frequency Counter
Count how often each word appears in Chinese text, sorted from most to least frequent, with an optional stop-word filter. Ideal for content analysis, runs locally and never uploads your text.
Chinese Text 11 uses
Chinese Text Statistics
Count characters, Chinese characters, punctuation, paragraphs, sentences and estimated reading time of Chinese text in real time. A handy tool for writing and submissions, processed locally.
Chinese Text 11 uses
Name Format Converter
Convert names between family-name-first and given-name-first orders, plus a surname, given-name form. Handles Chinese compound surnames and English names, fits author bylines and submissions.
Chinese Text 11 uses