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Solve small technical tasks without slowing down.

Use 50 focused online tools for data, APIs, CSS, server configuration, text, security checks and everyday coding work. Clear inputs, dependable output, and no unnecessary steps.

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50working tools
0accounts required
Freefor everyday use

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The collection is arranged by the kind of problem you need to solve, not by complicated product labels.

JSON & Data ToolsConvert, inspect, flatten and transform JSON and CSV data.14 tools API & Backend ToolscURL converters, JWT decoders, cron helpers and HTTP utilities.10 tools Web, Server & Code ToolsServer configs, permissions, subnetting, CSS and text utilities.26 tools

Popular tools

Reliable helpers for tasks that come up again and again.

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JSON Path FinderPopularFeaturedPaste JSON and instantly see every path in dot, bracket or JSONPath notation — click any path to copy it.JSON & Data Tools JSON Flatten & UnflattenPopularFlatten nested JSON into single-level dot-notation keys — or rebuild nested JSON from flat keys.JSON & Data Tools JSON to TypeScript InterfacePopularFeaturedPaste JSON and get clean TypeScript interfaces — with merged array shapes and optional-property detection.JSON & Data Tools Nested JSON to CSVPopularFlatten an array of nested JSON objects into a clean CSV with dot-notation column headers.JSON & Data Tools cURL to Fetch ConverterPopularFeaturedPaste any cURL command and get clean JavaScript fetch() code — headers, body, auth and all.API & Backend Tools JWT Expiry CheckerPopularInstantly see if a JWT is expired — with exact expiry time in your timezone, UTC, and remaining lifetime.API & Backend Tools JWT Claims DecoderPopularFeaturedDecode a JWT's header and payload with every registered claim explained — locally, nothing uploaded.API & Backend Tools Cron Expression HumanizerPopularType any cron expression and read what it means in plain English — instantly, as you type.API & Backend Tools

Worth keeping close

Useful tools for cleaner output, fewer mistakes, and faster decisions.

JSON Path FinderPopularFeaturedPaste JSON and instantly see every path in dot, bracket or JSONPath notation — click any path to copy it.JSON & Data Tools JSON to TypeScript InterfacePopularFeaturedPaste JSON and get clean TypeScript interfaces — with merged array shapes and optional-property detection.JSON & Data Tools cURL to Fetch ConverterPopularFeaturedPaste any cURL command and get clean JavaScript fetch() code — headers, body, auth and all.API & Backend Tools JWT Claims DecoderPopularFeaturedDecode a JWT's header and payload with every registered claim explained — locally, nothing uploaded.API & Backend Tools CORS Header GeneratorFeaturedGenerate correct CORS headers for Apache, Nginx, PHP or Express — with credential-mode validation built in.API & Backend Tools CHMOD CalculatorPopularFeaturedClick permission checkboxes and get the octal chmod value — or type an octal and see the permissions, live both ways.Web, Server & Code Tools

Useful without the usual clutter

Each page is built around a real task and explains what the result means.

Local processing is reviewed

Built-in tool JavaScript is checked for unexpected outbound requests. Sensitive tools also state their privacy and security boundaries on the page.

Fast from the first click

Open a tool, add your input, and get the result. There are no registration walls or deliberately hidden controls.

Limitations are part of the result

Important tools now show worked examples, edge cases, known limitations, review dates and the standards used to check the explanation.

Named ownership and maintenance

The site is owned and maintained by William, with a public testing methodology and changelog.

For quick checks

Decode a token, inspect headers, calculate a subnet, test a timestamp, or clean hidden characters before they cause trouble.

For reusable output

Generate CSS, redirects, security headers, code snippets and structured conversions that are ready to copy into a project.

For learning

Use the guides and on-page explanations to understand formats, browser behavior, server rules and safer implementation choices.

How the tools are checked

Examples of the evidence and boundaries published directly on high-impact tool pages.

Read the methodology

Reviewed September 3, 2026

Latest guides

Practical explanations that help you use the tools with confidence.

All guides

Sep 3, 2026 · Maintained by WilliamCIDR and IPv4 Subnetting: Worked Examples for DevelopersWork through /24, /26 and /30 networks step by step: masks, ranges, broadcast addresses, usable hosts and the boundaries calculators can and cannot infer.Sep 3, 2026 · Maintained by WilliamcURL to fetch(): Headers, Bodies, Auth and Multipart ExamplesTranslate common cURL requests into browser or Node fetch code while preserving method, headers, JSON bodies, form data and authentication intent.Sep 3, 2026 · Maintained by WilliamCHMOD 755 vs 644 vs 600: Permissions Explained with ExamplesDecode common Unix permission modes, see why files and directories need different execute bits, and avoid insecure recursive chmod fixes.

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