Developer Tools
Utilities for everyday development work: format and validate JSON, decode JWTs, generate UUIDs, encode and decode Base64 and URLs, convert timestamps, and more. Everything runs locally in your browser.
72 tools in this category.
Tools in Developer Tools
JSON Formatter
Format, beautify, and validate JSON with adjustable indentation — instantly in your browser.
Developer Tools
JSON Validator
Check whether your JSON is valid and find the exact line and column of any syntax error.
Developer Tools
JSON String Escape / Unescape
Escape a string for safe embedding inside a JSON document (handles quotes, backslashes, control characters), or unescape a JSON-encoded string literal back to its raw form.
Encoding Tools
UUID Generator
Generate cryptographically random UUID v4 identifiers, one or a thousand at a time.
Developer Tools
Email Validator
Check any email address for format errors, common typos, disposable providers, and role addresses — instantly in your browser.
Developer Tools
Base64 Encoder
Encode any text — including emoji and non-Latin scripts — into standard Base64.
Developer Tools
Base64 Decoder
Decode Base64 back into readable text, with clear errors for malformed input.
Developer Tools
URL Encoder
Percent-encode text for safe use in URLs — as a query value or a full URL.
Developer Tools
URL Decoder
Decode percent-encoded URLs and query strings back into readable text.
Developer Tools
JWT Decoder
Decode a JWT’s header and payload and check its expiration — without sending it anywhere.
Developer Tools
JWT Sign (HS256 / RS256)
Sign a JSON Web Token with HS256 (HMAC shared secret) or RS256 (RSA private key). Output is a standard compact JWT (header.payload.signature).
Security Tools
HMAC Generator
Compute a Hash-based Message Authentication Code (HMAC) for any message and shared secret. Supports SHA-256, SHA-512, SHA-1, and MD5. All computation runs in your browser.
Security Tools
Unix Timestamp Converter
Convert Unix timestamps to readable dates and back, with a live current-time readout.
Developer Tools
Regex Tester
Test and debug regular expressions with live matches, capture groups, and highlighted results.
Developer Tools
SQL Formatter
Format and beautify SQL queries for MySQL, PostgreSQL, SQLite, and more — with optional keyword uppercase and tab indentation.
Developer Tools
HTTP Status Code Lookup
Look up any HTTP status code from 100 to 511 with plain-language explanations, searchable and filterable by category.
Developer Tools
SVG Optimizer
Minify and clean up SVG markup from any source — strip editor metadata, remove default attributes, round numbers, and see the byte savings. Free, in your browser, no upload.
Image Tools
EMV TLV Parser
Decode an EMVCo tag-length-value payload into a readable tree. Same format used by PIX, QRIS, PromptPay, DuitNow, VietQR, and BharatQR.
Developer Tools
QR Modifier
Convert a static QRIS code to dynamic, set the transaction amount, edit the merchant name or city, and recompute the CRC — entirely in your browser.
Developer Tools
Luhn / PAN Validator
Validate a credit or debit card number with the Luhn checksum, identify the scheme (Visa, Mastercard, Amex, Discover, JCB, UnionPay), and generate a display-safe mask.
Developer Tools
ULID Generator
Generate ULIDs — sortable, URL-safe 26-character identifiers with a built-in timestamp. Free, cryptographically random, generated in your browser.
Generators
CSV to JSON Converter
Convert CSV to JSON and JSON to CSV instantly, right in your browser.
Data Tools
CSV Viewer
View any CSV as a sortable, searchable table — paste or drop a file, filter rows, and see column stats in your browser.
Data Tools
JSON Diff
Compare two JSON values semantically. Ignores key order, highlights added/removed/changed paths, and works with nested objects and arrays.
Developer Tools
JSONPath Query
Query any JSON document with JSONPath syntax — extract fields, filter arrays, count matches. A free, in-browser jq-lite for everyday JSON inspection.
Data Tools
TOML ↔ JSON Converter
Convert TOML to JSON and JSON to TOML, instantly in your browser. Useful for pyproject.toml, Cargo.toml, and any modern config file. Free, no upload.
Data Tools
Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes of any text instantly.
Developer Tools
UTM Builder
Add UTM campaign parameters to any URL so you can track traffic sources accurately in Google Analytics.
SEO Tools
Meta Tag Generator
Generate title, meta description, canonical, Open Graph, and Twitter card tags as ready-to-paste HTML.
SEO Tools
Sitemap Generator
Generate a clean XML sitemap for your website in seconds.
SEO Tools
robots.txt Generator
Generate a valid robots.txt with allow and disallow rules, sitemaps, and AI crawler directives.
SEO Tools
HTML Entity Encoder/Decoder
Encode special characters to HTML entities (& < > " ’) and decode named, decimal, or hex entities back to text.
Encoding Tools
Morse Code Translator
Translate text to Morse code and decode Morse back to text. Letter-perfect ITU/ANSI standard.
Encoding Tools
Base32 Encoder/Decoder
Encode text to Base32 and decode Base32 strings back. RFC 4648 alphabet, UTF-8 safe.
Encoding Tools
Cron Expression Parser
Parse a 5-field cron expression and see when it will next fire, with a plain-English explanation.
Developer Tools
JSON to YAML Converter
Convert JSON to clean YAML and decode YAML back to JSON. Round-trips common JSON shapes.
Data Tools
YAML to JSON Converter
Parse YAML into structured JSON, instantly in your browser. Useful for reading Kubernetes manifests, GitHub Actions workflows, and any YAML config.
Data Tools
HTML Minifier
Shrink HTML by stripping comments and collapsing whitespace. See byte savings in real time.
Developer Tools
CSS Minifier
Shrink CSS by stripping comments, collapsing whitespace, and tightening punctuation. See byte savings live.
Developer Tools
JavaScript Minifier
Quick JS minifier that strips comments and collapses whitespace. Best for trusted, simple code snippets.
Developer Tools
User Agent Parser
Identify the browser, OS, and device type from any user-agent string. Detects bots and crawlers too.
Web Tools
Cron Expression Generator
Build cron expressions from a simple form, or pick a common preset. See plain-English explanations.
Developer Tools
Number Base Converter
Convert between binary, octal, decimal, and hexadecimal. Type in any field and the other three update live.
Developer Tools
TOTP Code Generator
Generate time-based one-time passwords (2FA codes) from a Base32 secret. Same algorithm as Google Authenticator.
Security Tools
DNS Lookup
Query DNS records (A, AAAA, MX, TXT, NS, CNAME, SOA, CAA) for any domain using Google DNS-over-HTTPS.
Network Tools
IP Geolocation Lookup
Look up geolocation info for any IPv4 or IPv6 address — country, city, ISP, ASN, timezone. Free, runs in your browser.
Network Tools
CIDR Subnet Calculator
Calculate network, broadcast, mask, wildcard, and host range for any IPv4 or IPv6 CIDR block. Pure math, runs in your browser.
Network Tools
WHOIS / RDAP Lookup
Look up domain or IP registration info via RDAP. Registrar, status, dates, nameservers, contacts. Free, runs in your browser.
Network Tools
CSS Flexbox Playground
Visual playground for CSS Flexbox. Adjust container and item properties with sliders, see the live layout update, and copy the generated CSS.
Web Tools
CSS Grid Playground
Visual playground for CSS Grid. Define rows, columns, and gaps, place items by area or line number, and copy the generated CSS.
Web Tools
EXIF / Image Metadata Viewer
Read EXIF, GPS, IPTC, and other metadata from any image. See camera, lens, location, and timestamp. Your image never leaves your device.
Image Tools
HTML to PDF
Convert HTML to a PDF in your browser. Write or paste HTML, see a live preview, and download a print-ready PDF. No upload, no tracking, no server.
PDF Tools
Barcode Generator
Generate barcodes in 8 formats (EAN, UPC, Code 128, Code 39, ITF, MSI, Codabar, Pharmacode). Download as PNG or SVG. Runs in your browser, no upload.
Generators
CSS Box Shadow Generator
Visually design CSS box-shadows. Adjust offset, blur, spread, color, and inset. Stack multiple shadows for layered effects. Get the generated CSS instantly.
Web Tools
CSS Border Radius Generator
Visually design CSS border-radius values. Independent corner control, preset shapes, live preview, and copyable CSS. Includes the "organic" 8-value syntax.
Web Tools
JSON Tree Viewer
Paste any JSON and explore it as a collapsible tree. Click any value to copy it, or copy the whole path. Free, runs in your browser, no upload.
Developer Tools
Meta Tag Preview
See how your page will look in Google search results, Twitter, Facebook, and LinkedIn — before you publish. Type a title and description, upload an image, and the preview updates live.
SEO Tools
Markdown Editor
Write Markdown on the left, see the rendered HTML on the right. Live preview, character / word / line counts, copy HTML or Markdown, drag-drop a file to open it.
Text Tools
File Compressor (Zip / Unzip)
Create a zip archive from any files, or extract one — entirely in your browser. No upload, no signup, no file-size limits beyond what your browser can hold.
File Tools
API Tester (HTTP Requests)
Make HTTP requests from your browser: GET, POST, PUT, DELETE, with custom headers and body. Import a cURL command, see the full response (status, headers, body) with timing. Free, in browser, no signup.
Developer Tools
Image to Text (OCR)
Extract text from any image — screenshots, scanned documents, photos of signs. Choose a language, see the recognized text with confidence, and copy or download it. Free, in browser, no signup.
Image Tools
PDF OCR — Extract Text from Scanned PDFs
Pull text out of a scanned PDF in your browser. Each page is rendered at high resolution and recognized locally, with per-page text and a combined export. No upload, no signup.
PDF Tools
AES Encrypt / Decrypt
Encrypt or decrypt text with a password using AES-256-GCM. The encryption runs entirely in your browser, the password never leaves the page, and the result is a portable text envelope you can paste into an email, a chat, or a file.
Security Tools
Subtitle Converter (SRT, VTT, SUB)
Convert subtitles between SRT, WebVTT, and MicroDVD SUB. Paste or drop a file, pick the source and target format, and copy the converted text. Includes a timing-shift and a time-scale tool. Free, in your browser, no upload.
Media Tools
QR Code Decoder
Read the text or URL hidden in any QR code image. Drop in a screenshot, a photo, or a saved QR, and get the decoded payload. Detects URLs, emails, Wi-Fi credentials, and vCards. Free, in your browser, no upload.
Image Tools
Headline Analyzer
Score any headline on word count, character count, power words, sentiment, and clarity. Get a letter grade and a per-dimension tip. Free, in your browser, no upload.
SEO Tools
Writing Style Analyzer
Highlight adverbs, passive voice, complex words, and hard sentences in your text. Paste any draft and see the issues in real time. Free, in your browser, no upload.
Text Tools
Business Name Generator
Generate brand-name ideas for your startup, product, or project. Pick a style (modern, classic, playful, technical) and get a batch of names with the .com domain suggestion. Free, in your browser, no upload.
Generators
Random Name Generator
Generate random first and last names for mockups, test data, or placeholder content. Filter by gender (any, male, female, neutral) and region (English, Spanish, French, German, Japanese, Chinese, Arabic). Free, in your browser, no upload.
Generators
NewNetwork Latency Test
Ping several well-known endpoints from your browser and compare round-trip times to work out whether a slowdown is you or them.
Network Tools
NewFPS Benchmark
Measure your display's real refresh rate and frame delivery stability in a 10-second test.
Web Tools
NewScroll Performance Test
Auto-scrolls a sample panel at a constant speed and counts dropped frames, so you can see how smooth this device really is.
Web Tools