ToolMaster
Free Developer Tools Online
Essential developer utilities that run instantly in your browser. Format and validate JSON, encode/decode Base64, generate UUIDs, test regex patterns, decode JWT tokens, and test APIs — no account required, all private.
All 30 tools
JSON Formatter & Validator
Format, validate, and beautify JSON with syntax highlighting and error detection.
Base64 Encode / Decode
Encode and decode Base64 strings instantly with copy-to-clipboard support.
UUID Generator
Generate unique identifiers (UUID v4) for your applications and databases.
QR Code Generator
Generate customizable QR codes for URLs, text, and more. Download as high-quality PNG.
Hash Generator
Generate SHA256, MD5, SHA1, and other hash values from text input.
Regex Tester
Test and debug regular expressions with real-time matching and highlighting.
JWT Decoder
Decode and inspect JWT tokens client-side. No data sent to servers.
API Tester
Test REST APIs with a professional interface. Supports headers and raw JSON body.
HTML Formatter & Beautifier
Format, clean, and beautify raw HTML code. Indent nesting tags for readability.
CSS Formatter & Beautifier
Format raw CSS rules. Automatically add spacing, indents, and tidy style declarations.
SQL Query Beautifier
Format database queries. Align SELECT, JOINs, and WHERE clauses for better readability.
XML Formatter & Validator
Format and beautify XML strings. Validate XML documents and highlight syntax rules.
Epoch Timestamp Converter
Convert Unix epoch timestamps to human-readable dates and local timezones instantly.
Hex to RGB / RGBA Converter
Translate Hex color strings to RGB and RGBA formats, and preview opacity levels.
JS & CSS Minifier
Minify JavaScript or CSS files. Remove whitespaces and comments to compress file sizes.
Cron Expression Generator
Easily build crontab schedules using an interactive UI. Generate valid cron expressions.
.htaccess Redirect Generator
Generate standard Apache redirect rules, WWW rewrites, and basic config settings for .htaccess.
QR Code Scanner
Scan and decode QR codes from uploaded images client-side.
Barcode Generator
Generate barcode symbols including CODE128, EAN13, and UPC formats.
Barcode Scanner
Scan and decode barcodes from uploaded images client-side.
GitHub README Generator
Create highly professional GitHub profile or project README files.
Git Ignore Generator
Construct customized .gitignore templates based on SDKs and popular IDEs.
cURL to Fetch Converter
Convert standard CLI cURL commands into JavaScript Fetch API client requests.
cURL to Python requests Converter
Translate cURL request commands into Python requests code snippets.
JSON to CSV Converter
Convert JSON structures or lists to CSV format for spreadsheets.
CSV to JSON Converter
Convert CSV spreadsheets to structured JSON data lists instantly.
JSON Schema Generator
Generate standard schema declarations from JSON sample blocks.
JWT Generator
Generate custom JSON Web Tokens (JWT) for testing with custom secret keys.
Unix Permissions Calculator (chmod)
Calculate Unix chmod file permissions using visual rules or number values.
Docker Compose Generator
Visually select common services to output valid docker-compose.yml files.
Frequently Asked Questions
Are ToolMaster Free Developer Tools Online really free?
Yes. Every tool is 100% free with no usage limits, no watermarks, and no account required.
Do my files get uploaded to your servers?
No. ToolMaster processes files locally in your browser. Your data never leaves your device — unlike most competitors.
How is ToolMaster different from cloud-based tool sites?
ToolMaster runs entirely in your browser for maximum privacy and speed. No cloud upload means your confidential documents stay on your device.
Can I use these tools on mobile?
Yes. All tools work on Android and iPhone browsers — Chrome, Safari, and Firefox.
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