# Developer tools

> Nineteen everyday utilities that run entirely in your browser - what each one does, and why that makes them safe to paste a real token into.

Source: https://www.revquix.com/docs/tools/developer-tools
Last verified: 2026-09-04

---

Nineteen small utilities. **Every one of them runs in your browser** - no account, no credits, no
request, and they keep working with the network off.

Browse them at `/tools/category/developer`.

## What each one does

### Inspecting and decoding

| Tool                           | What it does                                                      |
| ------------------------------ | ----------------------------------------------------------------- |
| **JSON Formatter**             | Format, validate and minify.                                      |
| **JWT Decoder**                | Inspect a token's claims locally.                                 |
| **Base64 Encoder**             | Encode and decode text, URLs and files.                           |
| **URL Encoder**                | Percent-encode and decode, with the URL broken into its parts.    |
| **Timestamp Converter**        | Unix epoch to any timezone, and back.                             |
| **Number Base Converter**      | Binary, octal and hex - plus the signed reading of the same bits. |
| **Invisible Character Finder** | Why your diff shows every line changed, or why `===` says false.  |

### Matching and comparing

| Tool                    | What it does                                                  |
| ----------------------- | ------------------------------------------------------------- |
| **Regex Tester**        | Matches, capture groups, and an explanation of the pattern.   |
| **Diff Checker**        | Compare two blocks of text or code.                           |
| **Semver Range Tester** | Does `^1.2.3` match `1.3.0`? With the reason, not just a yes. |
| **Cron Explainer**      | Cron to plain English, plus the next ten runs.                |

### Generating

| Tool                    | What it does                                                           |
| ----------------------- | ---------------------------------------------------------------------- |
| **UUID Generator**      | v4, v7, and bulk generation.                                           |
| **Hash Generator**      | MD5, SHA-1, SHA-256 and SHA-512.                                       |
| **Case Converter**      | camelCase, snake\_case, kebab-case and nine more, all at once.         |
| **gitignore Generator** | A `.gitignore` for your stack, de-duplicated and grouped.              |
| **curl to Code**        | Turn a curl command into fetch, Python, Java, Kotlin or Go.            |
| **JSON to Types**       | TypeScript, a Java record, Kotlin, Go or Python from a sample payload. |
| **HTTP Status Codes**   | Every status code, what it means and when to use it.                   |

## They are safe to paste real values into

This is the practical reason to use these rather than the first search result.

> **Note** - The JWT decoder never sees your token
>
> It is decoded by JavaScript already on the page. Nothing is sent to us, so there is no server log it
> could land in and no request for anyone to intercept. The same holds for the hash generator, the
> base64 encoder - including its file mode - and everything else on this page.

The trade-off is the obvious one: since no run happens on our side, nothing is saved. These tools do
not appear in [your run history](https://www.revquix.com/docs/tools/your-run-history), and closing
the tab loses your input.

## Two more, not yet built

**Code Explainer** and **Error Explainer** are listed in the catalogue and marked Soon. Both will
call a model, so unlike everything above they will cost credits and need an account. Their pages
carry a Notify me field.

If you want either of those things today, the assistant in [Projects](https://www.revquix.com/docs/projects/ai-assist) already explains errors and code on a
file you are working in.

## Related

- [Money and tax tools](https://www.revquix.com/docs/tools/money-and-tax-tools) - The other browser-only set.

- [Projects](https://www.revquix.com/docs/projects/what-is-a-project) - When a snippet needs to become something you can run.