I built 40 free developer tools that run entirely in your browser (no login)

aibars — Fri, 02 Oct 2026 02:59:45 +0000

Every developer has the same routine: you need to format a JSON blob, decode a JWT, or check a cron expression, so you Google it and land on a different site each time. Some are slow, some want you to sign up, and some make you wonder where the data you just pasted is going.

I got tired of that, so I built DevTools Hub, a single place with 40 small tools for the things I reach for every day. Nothing you paste is uploaded to a server.

👉 https://devhub.aibars.net/en

Why "nothing is uploaded" matters

We paste sensitive things into online tools all the time: API responses, JWTs, SQL queries, config files. With DevTools Hub, your input is processed on your side and is not sent to a server. That means you can decode a token or format a query without worrying about who else might see it.

(Still, as a habit: don't paste production secrets into any website. Use test data when you can.)

What's inside

Formatters
JSON, SQL, YAML, XML, CSS and HTML formatters, plus JSON Diff and a live Markdown preview.

Text tools
Text Diff, Regex Tester, Case Converter and Text Stats.

Converters
Number base (binary, octal, decimal, hex), JSON ↔ CSV, HTML entities, Unix chmod calculator, timestamp converter and a CSS unit converter (px, rem, em, vw, vh).

Encoders
Base64, URL encoding, hash generator, image to Base64, JWT decoder/encoder and HMAC generator.

Generators
UUID, password, color converter (HEX, RGB, HSL), cron parser with next-run preview, QR code generator, Lorem Ipsum and a mock JSON data generator.

Reference and network
HTTP status codes, MIME types, ASCII table, URL parser and an IPv4 CIDR calculator.

Dev utilities
cURL to fetch/axios converter, timezone converter, byte size calculator (SI and binary) and a JSON Schema validator.

The principles I stuck to

No login. Open the page, use the tool, leave.
Free. All 40 tools are free to use.
No uploads. Your data stays with you.
One tool per page. Each page does one thing and loads quickly.

The ones I use most

JSON Formatter and JSON Diff when debugging API responses.
JWT Decoder to quickly check claims and expiry while testing auth.
Cron Parser, which previews the next runs so I stop guessing what */15 9-17 * * 1-5 means.
cURL to fetch/axios, because pasting a cURL command from the browser devtools and getting working code is a huge time saver.
Mock Data Generator for quickly creating realistic fake JSON for tests and demos.

What I'd love feedback on

Which tool do you use the most, and which one is missing?
Is there a tool you keep Googling that you wish lived in one place?

I'm adding tools based on what people ask for, so tell me in the comments and I'll look at it.

You can also find my other project, AIBARS, a daily AI news, open-source ranking and AI tools site.

Thanks for reading! 🙌

The fastest-growing open-source AI projects right now (and how I track them)

aibars — Wed, 30 Sep 2026 04:05:29 +0000

Keeping up with AI open source is a full-time job. Every week a new agent framework, MCP server or LLM tool shoots up GitHub. I got tired of jumping between news sites, GitHub trending and X threads, so I built a small site called AIBARS that tracks it all in one place.

Here is a snapshot of what its rankings show today (Sep 30, 2026).

Most starred AI projects

openclaw: ~390k stars
superpowers: ~292k stars
skills: ~270k stars
hermes-agent: ~249k stars
deepseek-harness: ~237k stars
n8n: ~206k stars

Fastest star growth

deepseek-harness: +3,408
skills: +2,198
ponytail: +1,906
cc-switch: +1,871
firecrawl: +1,678

What I noticed

Agent tooling dominates the charts. Agent harnesses, skills and workflow projects fill most of both lists. The attention has clearly moved from models to the tooling around them.
Total stars and star growth tell different stories. Some projects with huge star counts are barely moving, while smaller ones like ponytail and cc-switch are climbing fast. If you only look at the all-time list, you miss what is rising right now.
The same names show up twice. deepseek-harness and skills appear in both the most-starred and fastest-growing lists, which suggests momentum is compounding for a few winners.

Why I built it

I wanted a single page that answers "what actually matters in AI this week?" without opening ten tabs. AIBARS started as my own dashboard for that, and I've kept improving it for over a year.

Besides the open-source rankings, it has daily curated AI news, model rankings, 100+ AI tools and free learning resources. It is available in 6 languages: English, Simplified Chinese, Traditional Chinese, Japanese, Korean and German.

You can see the live rankings here: https://aibars.net/en/ranking

Your turn

What do you use to keep up with AI open source? And what would you want a site like this to show that it doesn't yet?

DEV Community: aibars