Developer tools · Local first · Built to grow
Better tools.Built fordevelopers.
JSON and data, encoding, generators, security, and image tools—extended with AI coding, code-model guidance, and app store assets. One focused toolbox built to keep growing.
Fast in the browser. Private by default. No account required.
Your tools
Pinned tools
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A focused workflow for app launches
App Store Assets
Compose store marketing screenshots, export exact App Store and Google Play sizes, and generate icon PNG sets from your existing logo—all locally in the browser.
01App Store Screenshot ComposerCompose headlines, backgrounds, and device frames around real app captures.02App Market Image ResizerCrop finished artwork to exact store presets and export an upload-ready zip.03App Icon Set GeneratorExport preset iOS, Android, and store listing icon PNGs from an existing logo.
Your screenshots and artwork stay in your browser throughout the workflow.
DA
Data Tools
Format, validate, and transform structured data.
Data Tools
JSON FormatterFree online JSON formatter and validator with Monaco, JSONPath, TypeScript/YAML tools, diff, schema validation, tree view, and local processing.
Data Tools
JSON Schema Generator from JSONFree JSON Schema generator from sample JSON: infer Draft 2020-12 or Draft 7, validate data locally in your browser—no upload.
Data Tools
SQL Formatter / SQL BeautifierFormat, beautify, and minify SQL queries online with local processing and dialect options for generic SQL, MySQL, PostgreSQL, SQLite, and T-SQL.
Data Tools
CSV to JSON / JSON to CSVConvert CSV, TSV, and JSON locally with header controls, delimiter options, type inference, table preview, copy, and download.
Data Tools
Text Diff CheckerCompare two text blocks locally with side-by-side or unified diff, line and word highlighting, ignore whitespace/case, and change statistics.
Data Tools
YAML Formatter / ValidatorFormat, validate, and convert YAML locally—Kubernetes, GitHub Actions, Docker Compose, JSON ↔ YAML, with line/column error hints.
Data Tools
XML Formatter / ValidatorFormat, validate, and minify XML with Monaco editing—syntax highlighting, error line markers, Maven POM, Android manifests, SVG, and sitemaps.
Data Tools
Unix Timestamp Converter OnlineFree online Unix epoch converter: paste 10- or 13-digit timestamps, get UTC, local time, ISO 8601, batch mode, and share links—100% in your browser.
EN
Encoding Tools
Encode and decode common developer formats.
Encoding Tools
Base64 Encoder / DecoderEncode and decode Base64 online—UTF-8, URL-safe, files, image paste, MIME wrap. 100% local.
Encoding Tools
URL Parser / Query BuilderParse URL parts, edit query parameters, and rebuild encoded URLs locally in your browser.
Encoding Tools
URL Encoder / DecoderEncode and decode URLs, URI components, form values, and query strings locally in your browser.
GE
Generator Tools
Generate IDs, passwords, and useful development values.
Generator Tools
UUID Generator OnlineFree UUID v4 generator online: create random IDs in your browser, copy one or batch, switch formats, and inspect existing UUIDs—nothing uploaded.
Generator Tools
Password GeneratorGenerate strong passwords and memorable passphrases locally with length, character sets, batch copy, and strength guidance.
Generator Tools
QR Code GeneratorGenerate QR codes from text or URLs locally in your browser. Choose size and error correction, then download PNG instantly.
WE
Web Tools
Inspect and prepare web content quickly.
Web Tools
Markdown Preview / Markdown to HTMLPreview Markdown online with GitHub Flavored Markdown support, inspect headings and links, then copy or download sanitized HTML locally.
Web Tools
CSS Unit Converter / Clamp GeneratorConvert px, rem, em, %, vw, and vh with configurable context, then generate fluid clamp() CSS for typography and spacing.
Web Tools
cURL to Fetch & Axios ConverterConvert cURL to JavaScript fetch or Axios online—paste from DevTools or docs, copy code locally. Does not send the HTTP request.
Web Tools
HTML Entity Encoder / DecoderEncode and decode HTML entities locally—named, decimal, and hex forms, batch lines, and text preview for CMS and frontend work.
Web Tools
Regex TesterTest regular expressions online with live match highlighting, capture groups, flags, and replace preview—100% local in your browser.
Web Tools
Color Picker & ConverterConvert colors between HEX, RGB, and HSL with live preview, WCAG contrast hints, copy buttons, and browser eyedropper support.
Web Tools
Cron Expression Parser OnlineParse cron expressions online into human-readable schedules, preview next run times locally, and build Unix crontab expressions.
SE
Security Tools
Inspect tokens, hashes, and security-related formats.
Security Tools
JWT Decoder OnlineDecode JWT tokens online and locally: view header, payload, exp/iat/nbf times, and signature limits without uploading tokens.
Security Tools
Hash GeneratorGenerate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes and HMAC digests for text and files locally—batch mode included.
IM
Image Tools
Crop, resize, and optimize images locally for docs, apps, and the web.
Image Tools
Image Cropper / Screenshot CropperCrop images and screenshots online in your browser—fixed ratios, custom output sizes, PNG/JPEG/WebP export. 100% local, no upload.
Image Tools
Image Compressor / WebP ConverterCompress images and convert to WebP, JPEG, or PNG in your browser—quality slider, resize, batch zip. 100% local.
Image Tools
Image Label Overlay / Brand Watermark CoverCover image corners or bottom labels with draggable brand-style overlay templates. Add clean badges, glass plates, icon labels, or stickers locally in your browser.
Image Tools
Responsive Image GeneratorGenerate multi-width WebP, JPEG, or PNG assets from one source image and copy srcset, picture, and Next.js Image snippets. 100% local.
Image Tools
Favicon / PWA Icon GeneratorGenerate favicon, Apple touch icon, and PWA PNG icons from one logo. Zip download + HTML link and manifest snippets. 100% local.
Image Tools
SVG Optimizer / Data URI GeneratorOptimize SVG, detect risky markup, and copy URL-encoded or Base64 Data URI and CSS background snippets. 100% local.