Ballpark

Calibrate unfamiliar numbers while you read. Click any underlined figure for context and comparisons.

You're reading that a cybersecurity startup raised a $28M Series B, a biotech enrolled 180 patients in its Phase II trial, or a hardware brand runs 34% gross margins. Is that big? Small? Normal for that field? If you don't live in the industry, you have no reference frame — and your existing intuition often misleads you. A 34% margin is alarming for SaaS but healthy for physical goods. A $28M Series B is small for AI but generous for security tooling. Ballpark gives you a quick directional sense, in place, without leaving the page — it underlines numbers as you read, and a click brings up a small card with context and comparisons. And it stays out of your way: Ballpark won't run on your email, bank, shopping, or internal work tools, so it only shows up where calibrating a number actually helps. FREE BY DEFAULT Ballpark has two free model options. Gemini Nano, a small AI model built into Chrome — free, no account, no key. If your device can't run it, Ballpark offers Google's free cloud model instead (needs a free Google key; no web search, and a daily limit applies). For the full experience, we recommend adding your own Claude (Anthropic) key so answers get faster, web-searched, and source-backed. Roughly 80–100 numbers per dollar — costing only about 1¢ per click. The exact cost varies with the page and whether a web search runs; you can track it on your Anthropic Platform dashboard. Every card names the engine that answered — you always know whether an answer searched the web or came from memory. GETTING STARTED A setup guide loads automatically when you add the Ballpark extension. The free on-device model may need a one-time download (about 4 GB) — the guide walks you through it. HOW IT WORKS - Free, open-source software (MIT license) — the default costs nothing; with a Claude key you pay only Anthropic for the calls you make - No Ballpark server. On-device answers never leave your browser; cloud calls go directly from your browser to Anthropic or Google — your data never passes through us - Finding and underlining numbers happens locally in your browser and is never sent anywhere Privacy policy: https://www.treebirdlabs.com/ballpark/privacy Source code: https://github.com/treebirdlabs/ballpark