Developer Tools

Fast browser-based tools for common developer tasks.

NeroTool's developer tools cover the small utilities that come up during everyday coding work — formatting and validating JSON, testing a regular expression, encoding or decoding Base64 and URLs, and generating UUIDs — without leaving the browser or installing a package.

Format & Validate

JSON Formatter & Validator

Format, validate and minify JSON directly in your browser.

Regex Tester

Test regular expressions against text and inspect matches.

Encode & Decode

Base64 Encoder & Decoder

Encode and decode UTF-8 text as Base64.

URL Encoder & Decoder

Encode and decode URL components and complete URLs.

Inspect & Preview

Open Graph Preview

Inspect Open Graph and Twitter Card metadata and preview social sharing cards.

SVG Sanitizer

Remove scripts, event handlers and unsafe SVG references in your browser.

SVG Metadata Remover

Remove common SVG metadata and authoring information locally.

Security

CSP Generator

Build a Content Security Policy header or meta tag locally.

Security.txt Generator

Create a security.txt file for responsible vulnerability reporting.

Generate

UUID Generator

Generate random UUID v4 identifiers.

Sitemap Generator

Generate an XML sitemap from website URLs.

Frequently asked questions

Can I validate JSON syntax online?

Yes, the JSON Formatter & Validator checks your JSON for syntax errors and formats it for readability, or minifies it for production use.

How do I test a regular expression?

The Regex Tester lets you enter a pattern and sample text, then highlights matches in real time so you can debug your expression.

What's the difference between Base64 and URL encoding?

Base64 encodes binary or text data into an ASCII string for safe storage or transfer, while URL encoding escapes characters so text can be safely included in a URL. Both tools are available on this page.

Are these developer tools free to use?

Yes, the JSON Formatter, Regex Tester, Base64 and URL encoders, UUID Generator, Sitemap Generator and CSP Generator are all free, with no account or sign-up required.

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