Free online developer tools
Free online developer tools that run entirely in your browser: JSON, YAML, Base64, JWT, regex, SQL, markdown, images, colours, dates, Nepali (Bikram Sambat) utilities and more. No sign-up, no uploads.
JSON & Data
Format, convert, diff and validate data
- CSV ViewerFree online tool to view your csv file.
- JSON CSV ConverterFormat JSON data to CSV and CSV to JSON format with our free online converter.
- JSON DiffCompare JSON data with our free online JSON diff tool.
- JSON Prettify/CompressUse our free JSON Formatter tool to beautify, validate, compress and edit JSON data online. Perfect for developers!
- JSON Query (jq / JSONPath)Free online jq playground and JSONPath tester. Filter, transform and extract JSON with jq 1.8 or JSONPath in your browser, with snippets and share links.
- Json Schema ValidatorValidates provided json data against provided json schema
- JSON to Language ConverterConvert JSON to PHP arrays, Python dictionaries, or Javascript objects, etc. effortlessly with our free online tool. Ideal for developers!
- JSON VisualizerVisualize JSON into interactive graphs
- JSON-XML ConverterConvert your json data to XML and vice versa
- JSON-YAML ConverterEasily convert YAML to JSON and JSON to YAML with our free online tool including support for yaml anchors. Fast and accurate conversion for developers.
- Json/JsonSchema -Typescript ConverterConvert your Json data or Json Schema to Typescript
- SQL FormatterFormat, beautify and minify SQL online for MySQL, PostgreSQL, SQLite, SQL Server, Oracle, BigQuery and more, with keyword casing and indent options.
- XML Prettify/CompressUse our free XML Formatter tool to beautify, validate, compress and edit XML data online. Perfect for developers!
- Yaml Lint-FormatterValidate and format YAML files with our free online tool. Ideal for developers and content creators.
Encoding & Security
Encoders, hashes, tokens and certificates
- Base64 Encoder/DecoderEncode and decode Base64 with our free online tool. Supports text conversions for developers.
- Certificate DecoderDecode X.509 SSL/TLS certificates in your browser: subject, issuer, SANs, validity, key usage, fingerprints, OCSP/CRL URLs. Verify chains and hostnames.
- CSR DecoderDecode certificate signing requests easily from your browser with our free online tool.
- CSR GeneratorGenerate certificate signing requests easily from your browser with our free online tool.
- Encryption & Key GeneratorGenerate RSA, ECDSA and Ed25519 keys as PEM, JWK or OpenSSH with fingerprints, encrypt text with AES-GCM or RSA-OAEP, sign with HMAC or keys and mint secrets.
- JWT Sign/VerifyDecode, Sign and verify JWT tokens with our free online tool.
- Number Base & Bitwise CalculatorConvert between binary, octal, decimal, hex and any base, run bitwise operations, calculate chmod and subnet masks, and inspect IEEE 754 floats.
- Password GeneratorGenerate strong and secure passwords with our free online password generator. Ideal for creating unique and random passwords for various applications.
- Secret HashGenerate secure hashes, HMAC, Scrypt, Blowfish, Bcrypt, PBKDF2 with our free online tool.
- SRI Hash GeneratorGenerate sha256/384/512 Subresource Integrity hashes for CDN scripts and stylesheets from a URL, file or pasted code, with the HTML tag and a verifier.
- URL Encoder/DecoderEncode and decode URLs with our free online tool
- URL Parser & Query EditorParse any URL into protocol, host, path, query and fragment, edit query parameters live, build UTM campaign links and export as JSON or cURL.
- UUID GeneratorGenerate unique identifiers with our free online UUID generator. Ideal for creating unique and random identifiers for various applications.
Code & Text
Beautify, preview and generate text
- Code BeautifyBeautify and format JavaScript, HTML, CSS and SQL code with our free online tool.
- Developer Test DataList of test data for developers, qa engineers and product people to use in their development and testing processes.
- Docker Run ↔ ComposeConvert docker run commands to docker-compose.yml and back, mapping ports, volumes, env, networks, healthchecks and GPUs, with warnings for unsupported flags.
- HTML ViewerView HTML code and render it online
- HTML-Markdown ConverterConvert HTML code to Markdown and Markdown to HTML format with our free online converter.
- LLM Token CounterCount tokens as understood by LLM models with our free online tool.
- Lorem IpsumGenerate lorem ipsum text content with our free online tool.
- Markdown Editor & PreviewWrite GitHub-flavoured Markdown with a live preview, highlighted code, tables and task lists. Autosaves drafts and exports to Markdown, HTML or PDF.
- Meta Tags & Social PreviewGenerate HTML meta tags, Open Graph, Twitter cards and JSON-LD, preview links on Google, Facebook, X, Slack and WhatsApp, and audit any page.
- Optical Character RecognitionRecognize text from uploaded file
- Regex TesterTest JavaScript regex online with live match highlighting, capture groups, find and replace, a plain-English explainer and code snippets for six languages.
- Text & String UtilitiesConvert text case (camelCase, snake_case, kebab-case), slugify, sort and dedupe lines, count words, and escape strings for JSON, HTML, SQL and shell.
- Text Diff CheckerCompare two texts or files online with line and word-level highlighting. Side-by-side or unified view, ignore case and whitespace, export as patch.
- Unicode InspectorInspect code points, UTF-8 bytes, escapes and blocks. Strip zero-width spaces, bidi controls and homoglyphs, normalize NFC and split Nepali aksharas.
Date & Time
Timestamps, cron and clocks
- Cron ParserParse classic and extended cron expressions with our free online tool.
- Date and TimeFind the current time and date of all timezones with our free online date and time tools.
- Epoch ConverterConvert epoch to date and date to epoch with our free online tool.
- Time / Stopwatch / Timer / AlarmTrack time, set alarms, use a stopwatch, and manage timers.
Image, Media & Design
Images, QR codes and recording
- Audio RecorderRecord your Audio
- Code ScreenshotTurn code snippets into beautiful shareable images in your browser: 39 languages, 10 colour themes, gradients, window chrome, line numbers, PNG/SVG export.
- Color pickerPick your desired color
- Color ToolsConvert HEX, RGB, HSL, CMYK, Lab and OKLCH colours, check WCAG and APCA contrast, generate palettes, gradients and shadows, and pick colours from images.
- Crop ImageFree online tool to crop your images
- CSS GeneratorsFree CSS generators with live preview: box shadow, gradient, glassmorphism, clip-path, transform, flexbox, grid, cubic-bezier, scrollbar. Copy CSS or Tailwind.
- Exif CleanerClean Exif data from your image
- EXIF viewerView EXIF data and various other metadata of images with our free online tool.
- File Type IdentifierIdentify the type of the uploaded file
- Image Converter, Compressor & ResizerConvert, compress and resize images in your browser: PNG to WebP, JPG to PNG, SVG to PNG, image to Base64 and favicons. Files never leave your device.
- PDF ToolkitMerge, split, reorder, rotate and watermark PDFs, convert images to PDF and PDF pages to PNG or JPEG, and edit metadata, all in your browser.
- Photo & Video RecorderCapture screenshots and record videos with audio using your webcam and microphone effortlessly with our free online tool. Ideal for creators and developers!
- QR Code Generate/DecodeGenerate and decode QR codes with our free online tool.
- Simple Image EditorEdit your image
- SVG Optimizer & ConverterOptimize SVG with SVGO in your browser, see bytes saved, then convert to React/Vue components, data URI, CSS background, symbol sprite or PNG, JPEG and WebP.
- WiFi QRGenerate and Download QR Codes to quickly connect to WiFi Networks
Network & Device
IP, CIDR and device information
- cURL ConverterConvert a cURL command to JavaScript fetch, axios, Python requests, Go, PHP, Ruby, Java, C#, Rust or PowerShell code, or turn a fetch() call back into cURL.
- List / Check IPv4 CIDRList or check ip addresses in the CIDR block
- My Device InfoSee your screen and browser resolution, device pixel ratio, aspect ratio, operating system and browser details, to debug responsive layouts.
- See My IPShow your IP information
Nepal
Bikram Sambat dates, Nepali text, numbers and data
- Nepal Address DataBrowse and export all 7 provinces, 77 districts, 753 local levels, 6,743 wards and postal codes of Nepal in English and Nepali as JSON, CSV, TypeScript or SQL.
- Nepal EMI & Loan CalculatorFree EMI calculator for Nepal: monthly instalment, total interest, amortization schedule with AD and BS dates, reducing vs flat rate and prepayment savings.
- Nepal Income Tax CalculatorCalculate income tax, monthly TDS and take-home salary in Nepal for FY 2080/81 to 2083/84 with SSF, PF/CIT, insurance and female rebate rules. Free, in-browser.
- Nepal Phone Number ValidatorValidate Nepali mobile and landline numbers, find the operator (NTC, Ncell) or district by area code, format as +977 E.164, bulk check lists and copy regex.
- Nepali Date Converter (BS ↔ AD)Free Nepali date converter: convert BS to AD and AD to BS, see today's Nepali date, calculate age and date differences, and batch convert lists.
- Nepali Font ConverterConvert Preeti, Kantipur and PCS legacy Nepali font text to Unicode and back, or type romanized Nepali to get Unicode Devanagari. Free and instant.
- Nepali Land Area ConverterConvert Nepali land area between ropani-aana-paisa-daam, bigha-kattha-dhur, sq ft, sq m, acre and hectare. Reads lalpurja notation and totals the land price.
- Nepali Number & Currency ToolsConvert numbers to Nepali and English words (lakh, crore, rupees and paisa for cheques), swap Devanagari digits, format amounts and calculate 13% VAT.
- Nepali Patro (Calendar)Nepali Patro: Bikram Sambat calendar with AD dates, Nepal public holidays and festivals for 2081–2084 BS, Dashain/Tihar countdown and ICS/CSV export.
- Nepali Test Data GeneratorGenerate fake Nepali test data: Devanagari and English names, real district/ward addresses, phone numbers, BS/AD dates, citizenship and PAN as JSON, CSV or SQL.
- Nepali Typing TestFree Nepali typing test for Lok Sewa: practise romanized, Traditional and Preeti layouts with live WPM, accuracy, per-letter errors, lessons and best scores.
- Nepali Unicode TypingType Nepali in English letters and get Unicode Devanagari instantly (namaste → नमस्ते), with smart phonetic spelling suggestions like Google Input Tools.
- NEPSE Share CalculatorCalculate NEPSE buy and sell costs: broker commission slabs, SEBON fee, DP charge, capital gains tax, bonus and right adjustment, WACC, dividend and break-even.