Online Toolbox
98 tools · Free online tools, ready to use
Dev 24 tools
JSON Formatter
Format, minify and validate JSON with error locating and one-click copy.
Timestamp Converter
Convert between Unix timestamp and datetime; auto-detect seconds/ms and show live current time.
UUID Generator
Batch-generate UUID v4 with dashed/lowercase/uppercase formats; copy all at once.
Hash Calculator
Compute MD5, SHA-1, SHA-256, SHA-512 of text or files, all locally with no upload.
Regex Tester
Test regular expressions online with live match highlighting and capture groups.
QR Code Generator
Generate a QR code from text or URL, with adjustable size and error correction; download as PNG.
Text Diff
Compare two texts line by line, marking added, removed and changed lines; great for config and code.
Cron Parser
Parse each field of a cron expression and compute the next 5 execution times.
JWT Decoder
Decode JWT header and payload; show issued time, expiry and remaining validity.
XML Formatter
Format or minify XML, check tag balance, with escape/unescape and structure stats.
JSON to CSV
Convert a JSON array to CSV, Markdown table or SQL; preview and download.
JSON Key Sorter
Recursively sort JSON object keys alphabetically and re-format for easier diff and reading.
Flex Layout Generator
Visually tune flex parameters with live preview and generate standard CSS; one-click copy.
Grid Layout Generator
Generate CSS Grid layout code visually with custom rows/columns and gap; live preview.
URL Parser
Break a URL into protocol, host, path, query params and hash for debugging and sharing.
Barcode Generator
Generate a barcode (CODE128/39, EAN, UPC and more) locally and download as SVG.
UUID v7 & Random MAC
Generate time-sortable UUID v7 and random MAC addresses (locally administered), for distributed IDs and masking.
JSON Path Extractor
Extract a value from JSON by dot path (e.g. user.name, tags.0), with nested objects and arrays.
JSON Diff
Recursively diff two JSONs, listing added/removed/changed field paths and values; great for API diffs.
CSV Column Extractor
Parse CSV and extract chosen columns by name, export a trimmed CSV; processed locally.
Cron Builder
Compose a cron expression field by field with common presets; complements the cron parser.
Batch QR Generator
Generate QR codes for many entries at once, displayed in a grid, each downloadable; rendered locally.
Random Port Generator
Generate random ports (1024-65535) labeled by class (system/registered/dynamic); local only.
Batch Timestamp Converter
Convert many Unix timestamps to dates at once, auto-detecting seconds/ms; local.
Encode & Crypto 17 tools
Base64 Encode/Decode
Convert text and Base64 both ways with correct UTF-8 Chinese; images preview as Base64.
URL Encode/Decode
Encode/decode URLs and parameter strings, for the whole URL or a single value.
Base Converter
Convert freely among binary, octal, decimal and hexadecimal, with big integers and bit view.
Color Converter
Convert HEX, RGB and HSL with a color picker and live preview; compare light/dark.
Unicode Converter
Convert Chinese and Unicode escape sequences both ways, supporting \uXXXX and \u{XXXXX}.
Random Password Generator
Batch-generate strong passwords with custom length and charset, plus strength estimate; local only.
WCAG Color Contrast
Check WCAG contrast ratio between foreground and background colors and whether AA/AAA pass.
QR Code Decoder
Upload an image with a QR code and decode it locally; the image is never uploaded.
AES Encrypt/Decrypt
Encrypt/decrypt text with AES-GCM; the key is derived locally from your password, nothing leaves the browser.
Password Strength Meter
Estimate password entropy and crack time, show the character pool and tips; local only.
Morse Code Converter
Convert between text and Morse code, with letters, digits and common punctuation.
Passphrase Generator
Build memorable, high-entropy passphrases from a built-in wordlist, with optional digits and symbols; local.
URL Safety Scan
Local heuristic scan for URL risks: plain HTTP, @ redirect, IP host, punycode, risky TLD, encoding obfuscation.
Username Generator
Generate random usernames from adjective+noun, with optional digits and separators; local.
Password Breach Check
Check a password against a built-in weak list and local rules (keyboard walk/sequence/repeat); no upload.
Password Audit
Audit a password in one go: strength (entropy) plus breach risks (weak list, keyboard walk, sequence, repeat); a full report.
Hash Verify
Compute MD5/SHA-1/SHA-256/SHA-512 of text and compare with an expected hash to verify integrity; local.
Text 17 tools
Word Count
Count Chinese/English characters, words, lines, paragraphs and Chinese punctuation; good for proofreading.
Text Case Converter
Convert among lower, upper, title, camelCase, snake_case and kebab-case naming.
Text Dedupe & Sort
Dedupe, sort, trim blank lines/spaces per line, and count occurrences.
Chinese Lorem Ipsum
Generate Chinese placeholder text for design and layout tests, in 4 styles: exposition, tech, news, marketing.
Random Picker & Grouper
Randomly draw, shuffle or split a candidate list into balanced groups; good for lottery and rolls.
Text Formatter
Clean text in one click: trim line edges, collapse spaces, remove consecutive blank lines.
Full/Half Width Converter
Convert between full-width and half-width characters, fixing mixed-width text in Chinese layouts.
Chinese Variant Converter
Convert between Simplified and Traditional Chinese (Taiwan/Hong Kong variants) with a local dictionary; no upload.
Chinese to Pinyin
Convert Chinese to pinyin with optional tones, per-character or joined; local dictionary.
Sensitive Word Checker
Scan text for sensitive words and count hits; built-in demo list plus your own words.
HTML Entity Encode/Decode
Encode and decode HTML entities for special characters, safe to display code and symbols on a page.
Line Number Tool
Add or strip line-number prefixes for pasted code, quotes and proofreading.
Text Case & Width
One-stop English case and full/half-width conversion: lower, upper, title, camel, snake, kebab, full, half.
Text Compliance Check
Count characters/CJK/English words/lines and highlight sensitive words (demo list + custom); local.
Emoji Search
Search emojis by Chinese/English keyword, click to copy; built-in dataset, local search.
Nickname Generator
Generate random nicknames from Chinese adjective+noun (+suffix); local, good for handles.
Word Frequency
Count frequency of CJK chars and English words, showing the top N in descending order; local.
Image 14 tools
Image Compressor
Compress images locally in the browser with adjustable quality and max dimension; batch supported, no upload.
Image Watermark
Batch-add text or image watermarks with adjustable position, opacity, rotation and tiling.
Image Joiner
Stitch multiple images vertically or horizontally into a long image; adjust gap, background and alignment.
Image Format Converter
Batch-convert among JPEG, PNG, WebP and BMP locally with no upload.
Seal Extractor
Detect the red seal area in an image, remove white background and noise, output a transparent PNG seal.
ID Photo Layout
Generate print sheets at standard sizes (1-inch, 2-inch, small 2-inch) ready to print.
Signature Extractor
Extract a handwritten signature from paper or contract photos to a transparent PNG, with auto crop.
Social Image Cropper
Batch-crop images to presets for WeChat, Xiaohongshu, Douyin, Bilibili, Taobao and more.
Image EXIF Viewer
Read a photo's EXIF: capture params, time, device and GPS; parsed locally, no upload.
Image Filter
Apply grayscale, invert, retro, warm filters and tune brightness/contrast/blur via Canvas; processed locally.
Palette Generator
Generate light/dark scales and complementary/analogous/triadic schemes from a base color; click a swatch to copy HEX.
Image to Base64
Convert images to/from Base64 data URLs with preview and download; processed locally.
Batch Image Compressor
Compress multiple images at once with adjustable quality, showing size change and download; local.
Image EXIF Stripper
Strip photo metadata (EXIF/GPS) by re-encoding via Canvas; download a clean image, local only.
Document 11 tools
Image to PDF
Merge multiple images into one PDF with adjustable page size, orientation and margin; drag to reorder.
PDF Merger
Merge multiple PDFs in a chosen order, with drag-to-reorder and delete.
PDF Splitter
Split a PDF by page range or one-page-per-file, with custom intervals and batch export.
Invoice Merge & Print
Arrange multiple PDF or image invoices on an A4 grid for printing; saves paper for reimbursement.
PDF Stamper
Stamp an electronic seal on a PDF, normal or cross-page, with position/size/opacity control.
PDF Page Remover
Remove selected pages from a PDF by page number with preview; processed locally, no upload.
Markdown to HTML
Render Markdown to HTML live and copy the source; handy for docs and blogs.
PDF Page Rotator
Rotate PDF pages by angle (all/odd/even), processed locally and downloaded; no upload.
PDF Page Extractor
Extract selected pages into a new PDF by page range, processed locally and downloaded.
PDF Page Reorder
Reorder PDF pages by a given sequence, processed locally and downloaded; no upload.
PDF Page Crop
Crop each page by margins, keeping the center content; processed locally and downloaded.
Life 15 tools
ID Card Info Extractor
Validate an ID card and extract birth date, gender, age, region, zodiac and constellation.
RMB Amount to Words
Convert an amount to standard Chinese capital numerals, precise to jiao/fen with proper rounding.
Phone Number Lookup
Detect carrier and number-segment type, validate format, with batch lookup.
Lunar/Solar Converter
Convert between solar and lunar dates both ways, with ganzhi, zodiac and traditional festivals.
Unified Social Credit Code
Validate a Unified Social Credit Code per GB 32100-2015; parse the registering department and region.
Bank Card Validator
Validate a card number with the Luhn algorithm and detect UnionPay, Visa, Mastercard and more.
Salary Tax Calculator
Compute take-home pay, social insurance and individual income tax with annual progressive rates, bonus included.
Mortgage Calculator
Compare equal-installment vs equal-principal repayment; output monthly payment, total interest and schedule.
Date Difference
Compute days, workdays and months between two dates, with add/subtract.
Unit Converter
Convert length, weight, area, volume, temperature, speed, data storage and more online.
Pomodoro Timer
Focus/break timer with adjustable duration; start, pause and reset; pure frontend, no login.
Countdown Timer
Set a target date and show live remaining days, hours, minutes and seconds; track multiple events.
BMI Calculator
Compute BMI from height and weight, classify underweight/normal/overweight/obese, with healthy range tips.
Number to Words
Spell out numbers in English (integers and decimals up to trillions); handy for invoices and copy.
Timezone Converter
Convert a date-time from one zone to major world zones; computed locally via Intl, no network.