Developer
Toolshelf provides free online developer utilities for decoding JWTs, testing regular expressions, building cron expressions, parsing User-Agent strings, and working with IP addresses. Every tool runs in your browser after the page loads — no account required.
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Chmod Calculator
Chmod calculator online. Convert Linux file permissions between octal (755), rwx symbolic, and a chmod command in your browser. Nothing is uploaded.
Cron Expression Generator
Online cron expression generator and explainer. Build, decode, and preview crontab schedules in your browser — no signup, no uploads. Runs locally on your device.
Docker Run to Compose
Docker run to Compose converter. Turn a docker run command into compose.yaml in your browser — ports, env, volumes, and warnings for unknown flags. Nothing is uploaded.
HTTP Status Codes
HTTP status codes lookup online, plus MIME types and a Basic Auth header builder. Runs in your browser. Passwords are not stored. Nothing is uploaded.
Tools in Developer Tools
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JSON Formatter & Minifier
JSON formatter online: beautify, minify, and validate JSON in your browser. Tree view included — no signup. JSON stays on your device.
Code Formatter & Beautifier
Online code formatter and beautifier. Format JavaScript, TypeScript, JSON, HTML, and CSS in your browser. Copy or download the result — nothing is uploaded.
SQL Formatter & Beautifier
Online SQL formatter and beautifier. Pretty-print or compact SQL in your browser for PostgreSQL, MySQL, SQL Server, BigQuery, and more. Queries are never executed or uploaded.
Related categories
- FormattersOnline formatters and beautifiers for code, SQL, and structured data. Format JavaScript, TypeScript, HTML, CSS, JSON, and SQL privately in your browser.
- EncodersBrowser-based encoders and decoders, including a Unicode-aware Base64 encoder, an image to Base64 converter, and a URL encoder with query-string parsing. Private, no signup.
- Color ToolsBrowser-based color tools to pick HEX, convert RGB and HSL, generate palettes and CSS gradients, mix shades and tints, and check WCAG contrast. Private, no signup.
Related guides
Frequently asked questions
- Can I decode a JWT here?
- Yes. Decoding is local and is not signature verification. Regex, cron, User-Agent, and IP tools also run in the browser.
- Does the chmod calculator change files on my server?
- No. It converts checkboxes, octal, and rwx strings and shows a command to copy. Nothing is applied over SSH.
Looking for something else? Browse all Toolshelf tools.