Format, Encode &
Debug Code Free
24 professional developer tools that run entirely in your browser. Format JSON, encode Base64, test regex, decode JWTs, generate hashes — all free, all private. No data ever leaves your device.
All 24 Developer Tools
Click any tool to start using it instantly. Every tool works in your browser — your code and data never leave your device.
JSON Formatter & Validator
Pretty-print and validate JSON with 2 / 4 space indentation.
JSON to CSV Converter
Convert JSON arrays to CSV format. Auto-detects columns, proper escaping, download as .csv.
CSV to JSON Converter
Convert CSV data to a JSON array of objects. Handles quoted fields and commas.
HTML Formatter & Minifier
Beautify messy HTML with proper indentation or minify it for production.
HTML Minifier
Minify HTML by stripping comments, collapsing whitespace. Shows size savings.
CSS Formatter & Minifier
Beautify CSS with proper indentation or minify it for production. Strips comments.
CSS Minifier
Minify CSS by stripping comments, collapsing whitespace, removing trailing semicolons.
JavaScript Formatter & Minifier
Beautify or minify JavaScript code. Strips comments, normalizes indentation.
JavaScript Minifier
Minify JS by stripping comments, collapsing whitespace. Shows compression stats.
Base64 Encoder & Decoder
Encode text to Base64 or decode Base64 back to text. Full Unicode and emoji support.
URL Encoder & Decoder
Encode special characters or decode percent-encoded URLs. Pure browser.
HTML Entity Encoder & Decoder
Encode special characters to HTML entities or decode entities back to text.
MD5 Hash Generator
Generate MD5 hashes from any text. Pure JS RFC 1321 implementation, runs in your browser.
SHA Hash Generator
Generate SHA-256, SHA-512 or SHA-1 hashes using the native Web Crypto API.
UUID Generator
Generate cryptographically random v4 UUIDs in bulk. Uppercase and no-dash options.
Regex Tester
Test regular expressions with live matching, capture groups and match highlighting.
Markdown to HTML Converter
Convert Markdown to clean HTML. Supports headings, bold, italic, links, code blocks, lists.
HTML to Markdown Converter
Convert HTML to clean Markdown. Handles headings, links, images, lists and code blocks.
JWT Decoder
Decode and inspect JSON Web Tokens. View header, payload, claims and expiration status.
Cron Expression Generator
Build cron expressions visually with plain-English descriptions and next-run preview.
JSON to YAML Converter
Convert JSON data to YAML format with proper indentation. Handles nested objects and arrays.
YAML to JSON Converter
Convert YAML data to JSON format. Validates YAML syntax and outputs clean formatted JSON.
SQL Formatter
Format and beautify SQL queries with proper indentation. Supports MySQL, PostgreSQL, SQLite and T-SQL.
JSON Path Tester
Test JSONPath expressions against JSON data. See matched results highlighted in real-time.
Why Developers Need Browser-Based Tools
Speed kills context-switching. Every time you leave your editor to open a separate JSON formatter or Base64 encoder, you break your flow. Browser-based tools load instantly in a tab — no installs, no package managers, no CLI flags to remember.
Privacy matters for production data. Pasting API keys, JWT tokens, or customer data into random online tools is a security risk. Our tools process everything locally in your browser using JavaScript and the Web Crypto API. Your data never touches a server — ever.
Beyond privacy, browser-based tools work offline once loaded. On a plane, in a cafe with spotty WiFi, or behind a corporate firewall — your JSON Formatter, Regex Tester, and Hash Generator all keep working without interruption.
For teams, shareable URLs mean everyone uses the same tools with zero setup. No "install this CLI" or "brew install that" — just send a link. Our JWT Decoder and URL Encoder are bookmarked by thousands of developers who need them daily.
Built For Every Dev Workflow
API Development & Testing
Format API responses, encode/decode payloads, and inspect JWTs without leaving your browser. Essential tools for every REST and GraphQL workflow.
Code Formatting & Minification
Beautify messy code for readability or minify production assets to shave kilobytes. Supports HTML, CSS and JavaScript with customizable options.
Security & Hashing
Generate secure passwords, create cryptographic hashes, produce UUIDs for database keys, and compute HMACs for API authentication signatures.
Data Conversion
Convert between popular data formats instantly. Transform JSON to CSV for spreadsheets, CSV to JSON for APIs, Markdown to HTML for publishing, and YAML to JSON for configs.
SlapMyWeb vs JSONLint / Others
Why use 10 different websites when one does it all?
How Our Developer Tools Work
- 1
Pick a tool
Choose from 24 specialized developer tools above — formatting, encoding, hashing, conversion, and more.
- 2
Paste your code or data
Paste JSON, Base64 strings, URLs, regex patterns, JWTs, or any data. Most tools auto-detect input format.
- 3
Get instant results
See formatted output, decoded values, matching highlights, or converted data in real-time. No waiting, no server round-trips.
- 4
Copy or download
One-click copy to clipboard or download results as a file. Your input is never stored — close the tab and it's gone.
Dev tools are just the start
These tools fix one thing each. Our AI scanner checks 240+ SEO signals across 10 pillars — performance, content, links, schema and more — in 30 seconds.
Run a free scanFrequently Asked Questions
Are these developer tools really free?+
Is my code and data safe?+
How does the JSON formatter handle large files?+
Can I use the regex tester for all flavors?+
Does the hash generator support all algorithms?+
Do these tools work offline?+
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