Developer tools that just work.
Format, decode, test and convert, right in your browser. No sign-up, no tracking of what you paste. Your data never leaves your machine.
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Formatters & converters
JSON Formatter
Beautify, minify, validate and sort JSON with clear error locations.
SQL Formatter
Beautify or minify SQL for PostgreSQL, MySQL, SQL Server and more.
YAML ⇄ JSON
Convert YAML to JSON and back. Great for Kubernetes and CI configs.
Timestamp Converter
Convert Unix epoch seconds or milliseconds to dates and back.
JSON to Types
Generate TypeScript, Java, Go or Python types from JSON.
JSON ⇄ CSV
Convert JSON to CSV and back, with nested fields and preview.
Markdown Preview
Write Markdown with a live preview. Export to HTML.
Case Converter
camelCase, snake_case, kebab-case, PascalCase and more, line by line.
Color Converter
HEX ⇄ RGB ⇄ HSL, palettes and a WCAG contrast checker.
Encoding & security
JWT Decoder
Decode header and payload, check expiry, verify HMAC signatures.
Base64 Encode / Decode
UTF-8 safe Base64 and URL-safe Base64 conversion.
URL Encoder & Parser
Percent-encode text and break URLs into their parts.
Hash Generator
MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hashes of any text.
SSL Certificate & SSH Key Decoder
Decode PEM certificates, chains and CSRs. Inspect SSH keys and known_hosts.
UUID Generator
Generate UUID v4 and time-ordered v7 identifiers in bulk.
Testing & debugging
Text Diff
Compare two texts and see every added, removed and changed line.
JSON Diff
Compare JSON by meaning: key order and formatting ignored, arrays matched by id.
Regex Tester
Live match highlighting, capture groups and replace preview.
Cron Expression Builder
Build cron schedules, read them in plain English, see next runs.
API Request Tester
Import a cURL command or build a request, inspect the response. Works with localhost.
Load Tester
Benchmark a local API with virtual users, latency percentiles and k6/JMeter script export.
DevOps & cloud
CIDR / Subnet Calculator
Network, broadcast and host ranges, AWS reserved IPs and a subnet splitter.
IP / CIDR Range Checker
Check which IPs fall in which ranges, find overlaps, range to CIDR.
AWS EventBridge Cron Builder
Build and validate 6-field AWS cron and rate expressions, see next runs.
Crontab ⇄ systemd Timer
Turn crontab lines into .service and .timer units, and back.
Chmod Calculator
Convert 755 ⇄ rwxr-xr-x, with setuid, setgid and sticky bits.
Dockerfile & Compose Validator
Lint Dockerfiles and docker-compose files for errors and bad practices.
GitHub Actions Builder
Generate CI/CD workflow YAML: tests, Docker, deploy to S3 or Pages.
.env ⇄ JSON / YAML
Convert dotenv files, plus K8s, Compose, ECS and GitHub Actions output.
HTTP Status Codes
Searchable reference of every status code, with when to use each.
User-Agent Parser
Detect browser, OS, device and bots from any User-Agent string.
Generators
Media & utilities
Floor Plan Designer
Draw house plans with walls, doors and furniture. Automatic room areas and a Vastu check.
Image Compressor & Converter
Compress, resize, crop and convert JPG, PNG and WebP. View and remove EXIF/GPS. Nothing uploaded.
Video Player
Play local videos and music with playlists, subtitles, speed control and resume. Nothing is uploaded.
Music Player
Play your music folder: albums, shuffle, playlists, equaliser, lyrics. Keeps playing in the background.
Drawing Board
Sketch, annotate screenshots and draw diagrams. Download as PNG, JPG or WebP.
Learning roadmaps
AWS Cloud roadmap
30 topics from IAM to Lambda and IaC, with projects, quizzes and progress tracking.
Kubernetes roadmap
33 topics from Pods to Gateway API, Helm, RBAC and GitOps. Maps to KCNA, CKAD, CKA and CKS.
DSA roadmap
33 topics from Big-O to graphs and dynamic programming, with 288 easy, medium and hard LeetCode problems to practise.
Sorting algorithms roadmap
17 topics from bubble sort to Timsort, each with a visualizer link and LeetCode problems.
DevOps roadmap
31 topics from Linux and Docker to CI/CD, Terraform, Kubernetes, monitoring and incident response.
Linux & Shell roadmap
22 topics from your first terminal to scripting, SSH, systemd and running a server. Maps to LFCS.
Git & GitHub roadmap
20 topics from your first commit to pull requests, rebasing, GitHub Actions and releases.
Sorting visualizer
Watch 10 sorting algorithms sort your own numbers step by step, or race two of them.
Games: take a break
Code Typing Test
How fast can you type real code? JS, Python, Java, SQL and Go.
XOX
Tic-tac-toe against an unbeatable AI, or with a friend.
Snake
The classic. Eat, grow, and don't bite your own tail.
2048
Slide and merge tiles to reach 2048. With undo.
Sumo
Charge, brace and push your rival out of the ring. Bot or 2-player.
Pen Fight
Flick your pen and knock your rival's off the desk. Bot or 2-player.
Carrom
Flick the striker, pocket your coins and cover the queen. Bot or 2-player.
Ludo
Roll a 6, race your four tokens home and capture rivals. 2–4 players or bots.
Cricket
Time your shots, find the gaps and chase the target. Bot or 2-player.
Snakes & Ladders
2–4 players, friends or bots, on one device.
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