Top 50+ Developer Tools You Must Have as a Developer (2026)

Every developer has the folder. Maybe it's called "tools," maybe "utils," maybe it's just forty tabs pinned across three browser windows. It grows one bookmark at a time — a JSON formatter found during an incident, a cron explainer found at 2am, a PDF merger found the day HR needed one document instead of six.

We're a software agency, which means our team's collective bookmark folder is somewhere north of ridiculous. This is the distilled version: the tools we actually reach for, with honest notes on why. All free (or meaningfully free), no affiliate links, no ranking drama — grouped by what you're trying to do.

The five we'd rescue from a house fire

1. regex101 — for regular expressions

The difference between regex101 and every other regex tester is the explanation panel: it decomposes your pattern token by token, in English, while you type. It's simultaneously a debugger and a teacher — after a year of using it, you'll need it less, which is the highest compliment a learning tool can get. Supports PCRE, JavaScript, Python and Go flavors, which matters more than people admit; the day you learn your pattern behaves differently in Python is a humbling one.

2. Excalidraw — for diagrams that don't look like committee output

Architecture diagrams have a dirty secret: the polished ones communicate worse. Excalidraw's hand-drawn style keeps diagrams looking like proposals instead of decrees, which changes how meetings react to them — people suggest edits to a sketch; they defer to a chart. Real-time collaboration and it works offline. We use it for everything from database schemas to explaining to clients why their spreadsheet is actually a database wearing a costume.

3. iLovePDF — for the document errands

Nobody loves PDF chores, and this does all of them: merge, split, compress, convert, rotate, watermark. The free tier covers normal human usage. One honest caveat that matters for some of our work: it processes files on their servers, so client contracts and anything under NDA shouldn't go through it — more on that class of problem at the end of this post.

4. JSON Crack — for JSON you can't read anymore

Past a certain nesting depth, raw JSON stops being human-readable — you're just counting braces and lying to yourself. JSON Crack renders it as an explorable graph. It's the difference between reading an API response and seeing it. Particularly good in code reviews and when onboarding someone onto an API they've never touched.

5. Pomofocus — for the discipline you don't have at 3pm

A pomodoro timer with exactly enough features: tasks, estimates, long-break intervals, and nothing else screaming for attention. The pomodoro technique itself is the real tool — 25 minutes of focus, 5 of rest — and Pomofocus is the least-annoying wrapper for it we've found. Whether pomodoro works for deep programming is a genuine debate (some problems need 90 unbroken minutes), but for grinding through tickets and email, it's undefeated.

The rest of the 50+, by errand

Formatting & data wrangling — JSONLint (validation with actually-useful errors), SQL Formatter (paste the 400-line query, get your dignity back), transform.tools (JSON→TypeScript types and 30 other conversions), Diffchecker (for text that isn't in git), TableConvert (CSV↔Markdown↔SQL tables).

Encoding, crypto & tokens — jwt.io (decode tokens, check expiry, stop guessing), Base64 Decode, CyberChef (the swiss army knife GCHQ inexplicably gave us all — chain 300+ operations), UUID Generator, a hash generator of your choice.

Time & scheduling — crontab.guru (the only reason anyone understands cron expressions), Epoch Converter (timestamps to dates without doing math in your head), Every Time Zone (scheduling calls between Jakarta and New York without the "wait, is that your Tuesday or mine").

Images, PDFs & media — TinyPNG (compression that pays your Lighthouse bills), Squoosh (side-by-side codec comparison, runs locally), remove.bg (background removal), SVGOMG (SVG optimization with a live preview).

Frontend & design — Can I Use (before you ship that CSS feature), Coolors (palette generation), CSS Gradient, Carbon (pretty code screenshots for docs and slides), Responsively (every viewport at once).

Docs & writing — readme.so (README structure without staring at a blank file), DevDocs (every API doc, one search box, works offline), Mermaid Live (diagrams as code, renders in GitHub).

API & network — Hoppscotch (open-source API testing that starts instantly), webhook.site (see exactly what that service sends you), DNS Checker (for the "is it propagated yet" hours of your life).

That's the neighborhood of fifty, and honestly the count undersells it — CyberChef alone is a few hundred tools in a trench coat.

The catch with fifty bookmarks

Here's what this list looks like in practice: fifty tabs, fifty domains, fifty variations of "is this site still up?" Half of them run your data through someone's server — fine for a color palette, less fine for a production JWT or a client's contract PDF. And precisely none of them work on a plane, in a basement server room, or during an ISP outage — which, if you're debugging in Indonesia during rainy season, is not a hypothetical.

That gap annoyed us long enough that we built our own answer: Gawe — 50+ of these utilities in a single tab. Formatters, encoders, hash and JWT tools, PDF and image utilities, a regex tester, cron builder, pomodoro timer, whiteboard. Everything runs locally in your browser: no data leaves your machine, it works fully offline, and it's free and open source, permanently.

We built it for our own team first — the tools above are great, and we still use several, but the daily-driver stuff deserved one tab with zero privacy questions. If your bookmark folder has also achieved sentience, give Gawe a look. And if it saves you some time, that's the whole point.