I built 47 free static dev tools with no backend — lessons learned

yeong j — Sat, 11 Jul 2026 01:58:28 +0000

Over the past few weeks I shipped 47 free browser-based tools for developers and sysadmins — cost calculators, config generators, converters. No backend, no build step, no framework. Just static HTML/CSS/JS on Cloudflare Pages.

Here's what I learned.

Why static-only

Every "free online tool" site I used had the same problems: slow, ad-stuffed, and quietly shipping my input to a server somewhere. For 90% of dev utilities that's absurd — a chmod calculator does not need a database.

So I set one constraint: everything runs client-side. If a tool can't work with the network tab empty, it doesn't get built. Paste a JWT into the JWT decoder and nothing leaves your browser. Load a tool once and it works offline.

That constraint turned out to be a feature, not a limitation:

Hosting costs $0. Cloudflare Pages serves static files for free, with a CDN included.
Nothing to maintain. No server to patch, no dependencies to bump, no 3am pages.
Deploys are git push. Build pipeline: none.

Lesson 1: one HTML file per tool beats a framework

Each tool is a single self-contained index.html — inline CSS, inline JS. I expected this to get painful around tool #10. It never did.

What I gained: zero shared state, zero build config, and any tool can be rewritten from scratch in an afternoon without touching the others. What I lost: some duplication (design tokens are copy-pasted into every file). I'll take that trade every time for a project like this — duplication is cheaper than the wrong abstraction.

Lesson 2: niche tools beat generic tools

My JSON formatter and password generator will never rank on Google — they compete with a hundred DR-90 sites. The tools that actually get found are the weirdly specific ones:

Game Server Cost Calculator — RAM and VPS cost by player count for Minecraft, Valheim, Rust
Fail2ban Jail Generator — pick services, get a ready jail.local
Docker RAM Calculator — size containers before picking a VPS plan

If I started over, I'd skip the generic utilities entirely and build only tools where I can name the exact person searching for it.

Lesson 3: static doesn't mean SEO-exempt

Pure-JS tool pages look "thin" to crawlers. What moved the needle:

Real written content on every page: a how-to section and an FAQ, not just the widget
FAQPage + WebApplication JSON-LD on every tool
Aggressive internal cross-linking — every tool links 3 related tools, so there are no orphan pages
Pairing each niche tool with a matching blog article that targets the informational version of the query

Lesson 4: i18n in ~60 lines of vanilla JS

The site is bilingual (EN/KO). I almost reached for a library, then wrote a tiny shared script instead: data-i18n attributes for short strings, .lang-en / .lang-ko blocks for long content, a toggle that flips a class on <html> and persists to localStorage. Sixty lines, no dependencies, works on every page.

The stack, in full

HTML/CSS/JS (vanilla, no build)
Cloudflare Pages (free tier) + Cloudflare Web Analytics (free, no cookies)
GitHub for deploys — push to main, live in ~1 minute

That's it. That's the whole stack.

What's next

More long-tail calculators, and following the search data to decide what to build instead of guessing. The full collection is at tools.stackfreeks.com — all free, no signup, nothing tracked beyond a page-view counter.

If you've built something similar (or think static-only is a mistake), I'd love to hear about it in the comments. And if there's a niche dev tool you wish existed — tell me, I might just build it.

DEV Community: yeong j