Wevva Tools · Instant Toolbox
Simple Online Tools. No login, no fuss—just click and solve.
Webmaster 10 tools
URL Parser
Break a URL into protocol, host, path, query params and hash for debugging and sharing.
Color Converter
Convert HEX, RGB and HSL with a color picker and live preview; compare light/dark.
WCAG Color Contrast
Check WCAG contrast ratio between foreground and background colors and whether AA/AAA pass.
URL Safety Scan
Local heuristic scan for URL risks: plain HTTP, @ redirect, IP host, punycode, risky TLD, encoding obfuscation.
View Source
Fetch a page source by URL; when CORS blocks it, open the native view-source in a new tab.
Baidu URL Push
Generate the Baidu webmaster API URL and curl command for proactive URL submission to speed up indexing.
My IP
Look up your public IP and location (city/ISP/timezone) via a public read-only API; pure frontend.
HTTP Status Codes
Look up the meaning of any HTTP status code (1xx-5xx) with common scenarios.
User Agent Toolkit
Parse your current UA (engine/OS/device) and copy common browser/spider UA strings.
IP to INT Converter
Convert IPv4 to/from 32-bit integer with hex and binary forms.
Develop 30 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.
Regex Tester
Test regular expressions online with live match highlighting and capture groups.
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.
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.
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.
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.
JSON Flatten
Flatten nested JSON objects into a single level of key-value pairs with a custom separator.
JSON Unflatten
Restore flat dot-notation keys back into nested JSON objects; numeric keys become arrays.
JSON to XML
Convert JSON data to a standard XML document with a custom root node; download as .xml.
XML to JSON
Parse XML into a JSON object; repeated tags become arrays; download as .json.
JSON to YAML
Convert JSON to YAML with proper indentation, lists and quoting of special values.
YAML to JSON
Parse indented YAML into JSON with nested objects, lists and auto-typed scalars.
JSON to Cookie
Turn a JSON object into a cookie string (key=value; ...) with optional URL encoding.
JSON Base64 Codec
Encode JSON to Base64 and decode back, UTF-8 safe so Chinese text never breaks.
JSON to SQL
Generate CREATE TABLE and batch INSERT statements from a JSON array with inferred column types.
SQL to JSON
Extract columns and values from INSERT statements into a JSON array, handling quoted commas and escapes.
JSON to Excel
Export a JSON array to a spreadsheet file (CSV, opens in Excel/WPS and can be saved as xlsx), BOM included.
Excel to JSON
Upload or paste spreadsheet content and convert it to a JSON array; custom separator supported, nothing is uploaded.
CSV to JSON
Convert headed CSV text into a JSON array with custom separator and quoted-field support.
Loading Spinner Generator
Generate CSS for spinner/dots/bars loading animations with live preview and copy.
Text 21 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.
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.
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.
ID Photo Date
Overlay a date stamp on an ID photo at any position — useful for old photo restoration.
Text on Circle
Arrange text along a circular path into an SVG with adjustable radius, size, color and direction; downloadable.
Xiaohongshu Sensitive Filter
Detect and highlight Xiaohongshu platform-limited/banned words, with one-click cleanup; built-in demo list plus custom words.
Idlefish Sensitive Filter
Detect and highlight Idlefish platform-limited/banned words, with one-click cleanup; built-in demo list plus custom words.
Email Validator
Batch-validate email format and flag disposable/temporary domains; done locally with no upload.
Mars Coordinate Converter
Convert among WGS-84 (GPS), GCJ-02 (Amap/Tencent) and BD-09 (Baidu) coordinates; computed locally.
Image 43 tools
QR Code Generator
Generate a QR code from text or URL, with adjustable size and error correction; download as PNG.
Barcode Generator
Generate a barcode (CODE128/39, EAN, UPC and more) locally and download as SVG.
Batch QR Generator
Generate QR codes for many entries at once, displayed in a grid, each downloadable; rendered locally.
QR Code Decoder
Upload an image with a QR code and decode it locally; the image is never uploaded.
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.
Image to PNG
Convert any common image format to PNG with alpha preservation, all locally in browser.
Image to JPG
Convert any image to JPEG with adjustable quality (1-100); transparent areas auto-filled white.
Image to WebP
Convert images to modern WebP format — typically 30% smaller than JPG and 50% smaller than PNG, with alpha support.
Image to BMP
Convert images to 24-bit uncompressed BMP, ideal for legacy software or hardware imports.
Images to GIF
Combine multiple images into an animated GIF with adjustable per-frame delay and width.
HEIC to JPG
Convert iPhone/Huawei HEIC/HEIF photos to universal JPG, decoded locally with no upload.
AVIF Converter
Decode AVIF and re-encode as JPG/PNG/WebP with adjustable output format and quality.
TIFF Converter
Decode TIFF/TIF and export as JPG/PNG; multi-page TIFFs support page selection.
PSD Preview
Read PSD/PSB files and export the composite (no per-layer editing), all local.
JXL to JPG
Attempt to decode JPEG XL and save as JPG (requires Safari 17+ or Chrome/Edge with experimental flag).
APNG to Frames
Split an APNG animated image into individual PNG frames for download and editing.
JP2 Converter
Convert JPEG 2000 (JP2/J2K) to JPG — prefers native decoding, falls back to WASM if needed.
ID Photo Sheet
Compose multiple small ID photos onto one A4 sheet with custom per-photo size and grid layout.
Stamp Merge
Remove white background from a stamp and overlay it onto any image with adjustable position, size and rotation.
Color Blindness Sim
Render images through protanopia, deuteranopia, tritanopia filters to test color accessibility.
Image Crop
Drag to select crop region with 8 resize handles for precise cropping; export as PNG.
Color Picker
Pick colors from any point of an image; show HEX/RGB/HSL and keep a swatch history.
Photo Frame
Add photo borders: classic white frame, Polaroid-style, colored gradient, drop shadow, etc.
Image Resize
Resize images by ratio / width / height / long-edge limit; export as PNG/JPG/WebP.
Image Rectify
Drag four corners to apply perspective correction to skewed documents/cards.
ID Photo Crop
Auto-center crop portraits to standard sizes (1" / 2" / passport / visa) with optional background color.
Image Grid Splitter
Slice an image into a 3×3 grid (or custom rows/cols) for social media posts.
Color Replace
Replace a chosen color (within tolerance) in an image with another color — handy for background swaps.
WeChat Group Live QR
Generate a group-invite QR code card; list multiple groups and export PNG (pure frontend makes a static code; dynamic routing needs a server).
WeChat & Alipay Pay QR Merge
Merge WeChat and Alipay payment QR codes into one image; upload QR images and export PNG.
Document 21 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.
PDF Batch Rename
Batch rename PDFs by prefix/suffix/number/replace/date patterns and download each.
PDF Scale
Adjust PDF page size to A4/A3/A5/Letter/B5 or scale by a percentage.
PDF Page Numbers
Stamp "Page X / Y" on each page at top-center, bottom corners or custom position.
PDF Compress
Remove redundant objects and metadata to shrink PDF size (browser-side has limits).
PDF to Images
Render every PDF page to PNG/JPG/WebP with adjustable DPI; download page-by-page.
PDF Watermark
Tile a diagonal text watermark across every page; adjustable size, opacity and rotation.
PDF Duplicate Pages
Scan every page fingerprint to find duplicates within the same PDF.
PDF to Word
Extract text from PDF and export as TXT / Markdown / simple DOCX (no layout fidelity).
Word to PDF
Convert .docx to HTML and render to PDF (simplified); complex styles may be lost.
Batch File Rename
Batch-rename any files by prefix/suffix/number/replace/case rules; processed locally and downloaded one by one.
Audio & Video 5 tools
Text to Speech
Read text aloud with the browser built-in speech synthesis; pick a Chinese voice and adjust rate/pitch, all local.
Decibel Meter
Measure ambient noise level in dB with your microphone; local only, never uploaded.
Voice Recorder
Record audio in the browser with pause/resume and preview; download locally.
Local Music Player
Play local audio files with playlist, playback speed and loop modes; fully local.
Local Video Player
Play local video files with speed, loop and frame screenshot export; fully local.
Life 22 tools
UUID Generator
Batch-generate UUID v4 with dashed/lowercase/uppercase formats; copy all at once.
UUID v7 & Random MAC
Generate time-sortable UUID v7 and random MAC addresses (locally administered), for distributed IDs and masking.
Full/Half Width Converter
Convert between full-width and half-width characters, fixing mixed-width text in Chinese layouts.
ID Card Info Extractor
Validate an ID card and extract birth date, gender, age, region, zodiac and constellation.
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.
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.
LED Text
Generate a neon scrolling LED text effect with adjustable color, speed and size; pure-frontend CSS animation.
Todo List
A locally-saved todo list with add/delete, done-state and clear; data stays in your browser.
License Plate Lookup
Resolve a license plate to its province and issuing city using a built-in nationwide plate table; local lookup.
WeChat Multi-Open Generator
Generate a WeChat multi-open batch file (.bat) to launch several instances at once; generated locally, never uploaded.
Retirement Pension Estimator
Roughly estimate retirement age, retirement year and monthly pension by current pension formulas; for reference only.
Keyboard Tester
Capture key presses and show key, code, keyCode and modifier states; handy for debugging keys.
Encode & Crypto 16 tools
Hash Calculator
Compute MD5, SHA-1, SHA-256, SHA-512 of text or files, all locally with no upload.
JWT Decoder
Decode JWT header and payload; show issued time, expiry and remaining validity.
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.
Hex & Binary Converter
Convert freely among binary, octal, decimal and hexadecimal, with big integers and bit view.
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.
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.
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.
HTML Entity Encode/Decode
Encode and decode HTML entities for special characters, safe to display code and symbols on a page.
Unit Convert 35 tools
RMB Amount to Words
Convert an amount to standard Chinese capital numerals, precise to jiao/fen with proper rounding.
Unit Converter
Convert length, weight, area, volume, temperature, speed, data storage and more online.
Currency Converter
Live ECB rates for 30+ currencies with amount conversion; falls back to built-in reference rates offline.
Shoe Size Converter
Convert shoe sizes between CN/EU/US/UK and centimeters for men and women.
Chinese Financial Uppercase Amount
Convert numeric amounts to Chinese uppercase RMB words for invoices and finance documents.
Blood Type Inheritance
Predict possible child ABO blood types from parents' types, with Rh notes.
Temperature Converter
Convert between Celsius, Fahrenheit, Kelvin and Rankine with a full-unit result table.
Time Unit Converter
Convert between ms, seconds, minutes, hours, days, weeks, months and years.
Weight Converter
Convert between ton, kg, g, jin, liang, pound, ounce, carat and more.
Volume Converter
Convert between m³, liter, gallon, pint, cup, fluid ounce and cubic feet.
Area Converter
Convert between km², hectare, mu, m², square feet and acre.
Sound Level Converter
Convert decibels to sound pressure (Pa) and pressure/power ratios.
Illuminance Converter
Convert between lux, foot-candle and phot illuminance units.
Length Converter
Convert between km, m, cm, li, chi, mile, foot, inch, nautical mile and light-year.
Frequency Converter
Convert between Hz, kHz, MHz, GHz and rpm.
Wind Speed Converter
Convert between m/s, km/h, mph, knots and ft/s with Beaufort scale reference.
Fuel Consumption Converter
Convert between L/100km, US/UK mpg and km/L.
Force Converter
Convert between newton, kilonewton, kilogram-force, ton-force, pound-force and dyne.
Torque Converter
Convert between N·m, kgf·m, lbf·ft and lbf·in.
Charge Converter
Convert between coulomb, millicoulomb, ampere-hour, mAh and elementary charge.
Capacitance Converter
Convert between farad, millifarad, microfarad, nanofarad and picofarad.
Resistance Converter
Convert between ohm, milliohm, kiloohm, megaohm and gigaohm.
Current Converter
Convert between ampere, milliampere, microampere and kiloampere.
Voltage Converter
Convert between volt, millivolt, kilovolt and microvolt.
Power Converter
Convert between watt, kilowatt, horsepower and BTU/h.
Pressure Converter
Convert between pascal, bar, atm, mmHg and psi.
Speed Converter
Convert between m/s, km/h, mph, knots, ft/s and Mach.
Angle Converter
Convert between degree, radian, gradian, arcminute, arcsecond and turn.
Energy Converter
Convert between joule, calorie, kilocalorie, Wh, kWh and BTU.
Density Converter
Convert between kg/m³, g/cm³, kg/L and lb/ft³.
CCT to RGB Converter
Convert color temperature (K) to approximate RGB/hex color.
Base Converter
Convert numbers between bases 2-36 with quick bin/oct/dec/hex presets.
REM to PX Converter
Convert between px, rem, em and percent with adjustable base font size.
Font Size Converter
Convert between px, pt, em, rem, percent, inch, cm and pica.
Bandwidth Converter
Convert between bps/Kbps/Mbps/Gbps and B/s/KB/s/MB/s.