// PROJECT — Developer Tools
ConverterHub
Solo design, build, and operation
ConverterHub is the tool site I wanted during on-call work: paste in a Unix timestamp, a JSON blob, or a Base64 string and get an instant answer without wondering where the data goes. It lives at converterhub.dev and bundles the everyday conversions developers and analysts reach for — timestamp ↔ date, JSON formatting and validation, JSON ↔ CSV, Base64 and URL encoding/decoding, case conversion, word/character counting, and text-to-SQL IN lists.
The defining decision was architectural: there is no backend at all. Every conversion executes client-side in the browser, so the data people paste — which is so often production data, tokens, or customer records — never crosses the network. No accounts, no login, no database, no server-side processing; the deliberate result is a utility site whose privacy guarantee is structural rather than a promise in a policy page. As someone who reviews web apps for a living, I wanted a site where the honest answer to 'what do you do with my data?' is 'nothing — we never receive it.'
The build itself is a lean Next.js App Router site: statically generated tool pages for speed and SEO, vanilla CSS with dark/light theming instead of a framework, a Vitest suite over the conversion logic, and per-tool metadata so each utility ranks for its own high-intent search query.
// Built With
// Highlights
- Seven everyday utilities in one place: timestamp converter, JSON formatter/validator, JSON ↔ CSV, Base64 & URL encode/decode, case converter, word & character counter, and text-to-SQL IN lists.
- 100% client-side execution — conversions run in the browser, so pasted data (often production data or tokens) never reaches a server.
- No-login by design: no accounts, no database, no tracking of tool inputs — the privacy guarantee is architectural, not a policy promise.
- Statically generated tool pages with per-tool SEO metadata, each targeting its own high-intent search query.
- Vitest suite over the conversion logic, with edge cases documented in a running decisions log.
- Minimal JS bundle and vanilla-CSS theming (dark/light) — fast enough to be the tab you keep pinned.
Security Considerations
- Zero data path to the server: the threat model for user data is eliminated rather than mitigated — there is nothing to breach, retain, or subpoena.
- Safe for sensitive inputs by construction — the site never receives the tokens, exports, or customer data users paste into converters.
- No third-party scripts in the conversion path, keeping the supply-chain surface of a paste-sensitive tool minimal.
Project Timeline
Stack & Privacy Decisions
Jan 2025Chose Next.js + TypeScript with vanilla CSS, and made the defining call recorded in the decisions log: no database, all tools client-side only — privacy, low latency, zero backend cost.
Core Tool Build
Jan 2025Built the first wave of converters — timestamps, JSON formatting/validation, Base64/URL, case conversion — as statically generated pages sharing one conversion-engine pattern.
Launch on converterhub.dev
Feb 2025Shipped to Vercel on a custom domain with dark/light theming, per-tool metadata, sitemap, and a Vitest suite over the conversion logic.
Analyst Tools
Apr 2025Added the JSON ↔ CSV converter, word/character counter, and text-to-SQL IN list — the requests that kept coming from data-analyst workflows.
Content & Upkeep
Jun 2026Added about, privacy, and blog pages, refreshed dependencies, and kept the bundle lean — the site stays fast enough to live as a pinned tab.