ToolHub: 500+ Free Tools in One Search Box

Inspiration

Everyday questions like "How much will this loan cost?" or "How much protein do I need?" send people bouncing between dozens of ad-filled sites. I wanted one clean place for all of them, for students, investors, business owners and anyone else. This fits the theme of "Productivity" because it saves people time by putting every calculation in one place

What it does

ToolHub is a search-first toolbox with 500+ free tools in 24 categories, including finance, business, health, math, science, construction, travel, food and converters. Type what you need, open the tool, change the numbers and the result updates instantly. You can filter by audience (Students, Investors, Businesses, Everyone), save favorites and see recently used tools. Everything runs in your browser, so nothing is sent to a server.

How I built it

The tools are data, not hand-written pages. A few engines (a formula calculator and a unit converter) read each tool's JSON definition: its inputs, formulas and outputs. That means I can add a new tool by adding data instead of code. I built the app in Google AI Studio (Gemini), used Claude to generate and check the tool data in batches, and stored everything on GitHub.

Challenges

Keeping 500+ tools correct and free of duplicates. I validated every formula, checked results against default values and removed repeats by slug. I also had to work within free AI usage limits, which pushed me to use the data-driven design.