I've been building Flowelio, a growing suite of free calculators
and tools with one hard constraint: everything runs client-side.
No servers, no file uploads, no accounts — just the browser.
What's in it right now:
- Health: BMI, TDEE, body fat, pace calculator, 1RM, race predictor
- Finance: compound interest, ROI, break-even, carbon footprint, solar savings
- Utility: password generator, unit converter, timezone, percentage, split bill
- Italy-specific: net salary (with full IRPEF/INPS breakdown), flat tax regime,
NASpI unemployment, property tax (IMU) for all 8,100+ Italian municipalities,
car tax by region, fiscal code generator/validator
- AI tools: background removal and depth map estimation — both running
entirely in the browser via Transformers.js + WebGPU, zero uploads
The Italian tax tools were the most interesting engineering challenge.
Italy has 8,100+ municipalities, each with its own property tax (IMU) rate
set by local government. Rather than fetching this at runtime, I baked all
the data into static JSON files and used Angular's SSG to pre-render a
dedicated HTML page for every single municipality at build time.
The result: ~8,400 static pages deployed to Cloudflare's edge,
sub-50ms TTFB globally, zero infrastructure cost.
The privacy angle came naturally from the architecture — when there's
no server, there's nothing to leak. The AI tools make this concrete:
background removal competitors like remove.bg upload your photo to their
servers. Ours processes everything locally with ONNX Runtime + WebGPU.
More countries (US, UK, DE, FR, ES, CA, AU, IN, BR) and dev tools
(JSON formatter, regex tester, diff checker, SQL playground) are in progress.
Happy to discuss the SSG strategy, the tax data pipeline, or the
client-side AI approach. Would love to hear what tools you'd find
most useful.
5 comments
[ 5.7 ms ] story [ 41.4 ms ] threadI've been building Flowelio, a growing suite of free calculators and tools with one hard constraint: everything runs client-side. No servers, no file uploads, no accounts — just the browser.
What's in it right now: - Health: BMI, TDEE, body fat, pace calculator, 1RM, race predictor - Finance: compound interest, ROI, break-even, carbon footprint, solar savings - Utility: password generator, unit converter, timezone, percentage, split bill - Italy-specific: net salary (with full IRPEF/INPS breakdown), flat tax regime, NASpI unemployment, property tax (IMU) for all 8,100+ Italian municipalities, car tax by region, fiscal code generator/validator - AI tools: background removal and depth map estimation — both running entirely in the browser via Transformers.js + WebGPU, zero uploads
The Italian tax tools were the most interesting engineering challenge. Italy has 8,100+ municipalities, each with its own property tax (IMU) rate set by local government. Rather than fetching this at runtime, I baked all the data into static JSON files and used Angular's SSG to pre-render a dedicated HTML page for every single municipality at build time. The result: ~8,400 static pages deployed to Cloudflare's edge, sub-50ms TTFB globally, zero infrastructure cost.
The privacy angle came naturally from the architecture — when there's no server, there's nothing to leak. The AI tools make this concrete: background removal competitors like remove.bg upload your photo to their servers. Ours processes everything locally with ONNX Runtime + WebGPU.
More countries (US, UK, DE, FR, ES, CA, AU, IN, BR) and dev tools (JSON formatter, regex tester, diff checker, SQL playground) are in progress.
Happy to discuss the SSG strategy, the tax data pipeline, or the client-side AI approach. Would love to hear what tools you'd find most useful.