Free Online Tools · 100% Local Processing
Image conversion · PDF · text tools · encoding · color · calculators · QR code · and more. Files never leave your device — more private, faster.
🔒 Why we insist on 100% local processing
- Privacy:Your files never leave the browser, eliminating leakage risk.
- Speed:No upload/download waiting; speed depends on your device.
- Low cost:Pure static hosting on Tencent Cloud EdgeOne — zero server load, tools free forever.
- Offline:Most tools still work offline once the page loads.
🖼️ 图片工具 格式转换 / 缩放 / 水印 / ICO / 滤镜 / 拼接 View all 23 ›
Image Format Converter
Upload an image, choose the target format (PNG/JPEG/WEBP/BMP), and convert & download locally in one click.
PNG to JPG
Convert PNG to JPG locally — smaller size, no upload.
JPG to PNG
Convert JPG to PNG locally — lossless, no upload.
PNG to WEBP
Convert PNG to WEBP locally — smaller size, no upload.
WEBP to PNG
Convert WEBP to PNG locally — lossless, no upload.
JPG to WEBP
Convert JPG to WEBP locally — smaller size, no upload.
WEBP to JPG
Convert WEBP to JPG locally — no upload.
PNG to BMP
Convert PNG to lossless BMP locally — no upload.
JPG to BMP
Convert JPG to lossless BMP locally — no upload.
BMP to PNG
Convert BMP to PNG locally — lossless, no upload.
GIF to PNG
Convert GIF to a static PNG locally — no upload.
Image Resizer
Resize images by ratio, width, or custom dimensions locally and download.
Image Watermark
Upload an image, add a text or image watermark, adjust opacity & position, export locally.
Image Compressor
Compress images locally, adjust quality/width, show savings and download.
Image Cropper
Crop images by selecting a region locally, ratio & batch supported.
Image Rotate / Flip
Rotate images any angle / 90° multiples locally, mirror & batch.
Image to ICO
Convert an image to a multi-size .ico favicon locally.
Image to Base64
Convert images to/from Base64 locally, copy Data URI or restore.
Image Filter
Apply grayscale/retro/invert filters locally and download.
Image Collage
Join multiple images horizontally/vertically/grid locally.
EXIF Viewer / Stripper
Read photo EXIF locally and strip metadata before re-download.
Image Color Extractor
Extract a main-color palette from an image locally, copy HEX.
Image Border
Add border and rounded corners to an image locally, preview and download.
📄 文档 / PDF PDF 转换 / 合并 / 水印 / 压缩 / 旋转 View all 13 ›
PDF to Image
Upload a PDF, render each page to an image locally and download — no upload.
PDF Merge
Select multiple PDFs and merge them into one file locally.
PDF Split
Upload a PDF, split by page or range locally, download as ZIP.
PDF Watermark
Upload a PDF, tile a text watermark locally and download.
Word to PDF
Render Word (.docx) to PDF locally and download — Chinese text intact.
Excel to PDF
Render each Excel sheet to PDF locally and download.
PPT Text Extractor
Unpack PPT locally, extract text & notes per slide, export as text.
PDF Page Numbers
Add page numbers to every PDF page locally and download.
Image to PDF
Merge multiple images into one PDF locally and download.
PDF Compressor
Compress PDF by lowering image quality locally, show savings, batch.
PDF Rotate
Rotate PDF page orientation locally and download.
PDF Text Extractor
Extract PDF text locally with pdf.js, copy or download .txt.
PDF Delete Pages
Delete specified PDF pages locally (ranges supported), keep the rest.
🧮 计算器 科学计算 / 房贷 / 个税 / 复利 / 单位 View all 10 ›
Scientific Calculator
Local scientific calculation with functions and constants — works offline.
Mortgage Calculator
Compute mortgage monthly payment, total interest and repayment (equal installment).
Percentage Calculator
Compute percentages, ratios and changes locally.
Unit Converter
Convert length, weight and area units locally.
Date Calculator
Compute date difference and date +/- days locally.
BMI Calculator
Compute BMI and body-type reference from height & weight.
Tip Calculator
Compute tip and per-person amount locally, multi-person split.
Age Calculator
Compute exact age and days since birth locally.
Income Tax Calculator
Compute income tax and take-home pay locally by progressive rates.
Compound Interest Calculator
Compute maturity and total interest by compounding frequency.
🎨 配色设计 取色 / 配色 / 对比度 / 色卡 / 代码转换 View all 4 ›
Color Design Toolkit
Generate harmonious palettes, check contrast, pick colors from images, make gradients.
Color Code Converter
Convert HEX/RGB/HSL in real time locally and copy.
Color Palette Generator
Generate harmonious palettes from a base color locally.
Contrast Checker
Compute foreground/background contrast and check WCAG AA/AAA.
🛠️ 效率工具 二维码 / 随机 / 番茄钟 / 密码 / 计时 View all 9 ›
QR Code Generator
Enter text/URL, generate a QR code locally and download PNG.
Random Decision
Draw randomly from options, or flip a coin for two choices.
Webpage Screenshot
Capture a webpage screenshot (limited by CORS; planned).
即将上线
Password Generator
Generate strong passwords locally with crypto randomness, configurable.
Countdown / Stopwatch
Local countdown & stopwatch with custom duration and controls.
Random Number Generator
Generate range/count controlled random integers locally, dedupe & sort.
QR Code Decoder
Recognize a QR image locally and extract URL/text.
Pomodoro Timer
Local pomodoro cycles, custom focus/break duration.
Password Strength Checker
Evaluate password strength and checks locally, estimate entropy.
📝 文本工具 字数 / 大小写 / 排序 / 对比 / 查找替换 / 转语音 View all 9 ›
Word Counter
Paste text, count words, characters, lines and paragraphs locally.
Case Converter
Convert English case and full/half-width locally.
Text Sort & Dedupe
Sort lines, dedupe, remove blank lines and count lines locally.
Text Diff
Compare two texts line by line locally, highlight additions & deletions.
Find & Replace
Batch find & replace text locally, case & regex supported.
Text to Speech
Read text aloud locally with browser TTS, adjustable speed.
HTML Entity Encode / Decode
Convert text and HTML entities locally, prevent XSS & garble.
Markdown Preview
Render Markdown to HTML locally in real time, copy the result.
Lorem Ipsum Generator
Generate Lorem Ipsum of chosen paragraphs locally.
💻 编码 / 开发 JSON / Base64 / URL / 时间戳 / 哈希 / UUID / 正则 / 进制 View all 13 ›
JSON Formatter / Validator
Format, minify and validate JSON locally, with error line location.
Base64 Encode / Decode
Encode/decode text & images to Base64 locally, Chinese supported.
URL Encode / Decode
Percent-encode and decode URLs/text locally.
Timestamp Converter
Convert between timestamp (sec/ms) and date-time locally.
Hash Calculator
Compute MD5/SHA1/SHA256/SHA512 digests locally.
UUID Generator
Generate batch UUID v4 locally with crypto randomness.
Regex Tester
Test regex match/replace locally, highlight hits.
Base Converter
Convert between binary/octal/decimal/hex locally, big int.
RMB Uppercase
Convert numeric amounts to Chinese capital locally, copy-ready.
JWT Decoder
Decode the three JWT parts locally and pretty-print.
Cron Parser
Parse cron meaning and predict next runs locally.
CSV ↔ JSON Converter
Convert CSV and JSON both ways locally, multiple delimiters.
AES Text Encrypt / Decrypt
Encrypt/decrypt text locally with AES-GCM, passphrase stays local.