Show HN: Prism.Tools – Free and privacy-focused developer utilities
by BLGardner | 2026-01-06 12:33:49+00:00
Hi HN, I'm Barry and I've built Prism.Tools (https://blgardner.github.io/prism.tools/) – a collection of client-side developer utilities that respect your privacy.

Many of these tools were used way back in the days when I ran a BBS and started my communities first ISP, serving three local communities with Dial-Up Internet, Web Hosting etc. The tools have been refined to reflect the changes in tech since then and designed for the Novice and Pro alike. As I locate more tools others may find useful I will refine and add them to the collection. Use them, Share them, or not. They will be here if you need them...

40+ dev tools (JSON formatters, regex tester, base64 encoder, Git command helper, etc.) that run entirely in your browser.
Zero tracking, zero analytics, zero data collection – everything processes locally.
Self-contained HTML files with no build process or frameworks.

I realized I had a lot of tools/utilities I've built over the years for my own use. I lothe having to 'sign-up' just to access/use simple utilities that I can create myself. I've refined them and put them in one safe place so I could easily access them if/when needed. I decided to make them available via Github Pages for anyone that may find them useful. Prism.Tools is the result.

Each tool is a standalone HTML file with embedded CSS and JavaScript. No frameworks, no npm packages, no build steps – just open the file and it works.

The entire toolset:

- 100% client-side processing – your data never leaves your browser.

- No external dependencies except for specific libraries from cdnjs.cloudflare.com (marked.js for markdown, exifr for image metadata, etc.)

- Consistent dark UI – every tool follows the same design language for familiarity.

- Vanilla JS where possible – only reaching for Public CDN Resources when necessary.

The constraint of "single HTML file" was intentional. It forces simplicity and ensures tools remain maintainable. It also means users can inspect, modify, or self-host any tool trivially.

These tools have helped me with debugging production issues, Quick formatting tasks, learning Git commands (the Git command helper has been particularly helpful)

Just visit https://blgardner.github.io/prism.tools/ and try any tool. No signup, no install.

What tools are missing that you find yourself needing?
Any performance issues with specific tools?
UI/UX friction points?

All tools follow the same privacy-first philosophy...
Your data stays in your browser. No accounts, no tracking, no servers processing your information.
The project is also a demonstration that you don't always need React, Vue, or complex build pipelines – sometimes vanilla JavaScript in a single HTML file is exactly the right tool for the job.

Vanilla JavaScript (ES6+)
CSS3 with CSS Grid
Minimal external libraries: marked.js, exifr, highlight.js, sql-formatter (all from CDN)
No frameworks, no bundlers, no npm
Hosted on Github Pages

Happy to answer questions about the technical implementation, design decisions, or specific tools!

All tools are inspectable – just view source on any page to see exactly how they work!