Overview
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. COST Roughly 80–100 numbers per dollar — 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. GETTING STARTED A setup guide loads automatically when you add the Ballpark extension. With an API key ready, setup takes <1 min. To reopen the setup guide anytime, click the Ballpark icon via the Extensions (puzzle-piece) menu. HOW IT WORKS - Free, open-source software (MIT license) — you pay only Anthropic for the calls you make - Requires your own Anthropic API key — calls go directly from your browser to Anthropic. There is no Ballpark server, and 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
Details
- Version1.1.0
- UpdatedJune 15, 2026
- Offered byTree Bird Labs
- Size51.17KiB
- LanguagesEnglish
- Developer
Email
treebirdlabs@gmail.com - Non-traderThis developer has not identified itself as a trader. For consumers in the European Union, please note that consumer rights do not apply to contracts between you and this developer.
Privacy
Ballpark has disclosed the following information regarding the collection and usage of your data. More detailed information can be found in the developer's privacy policy.
Ballpark handles the following:
This developer declares that your data is
- Not being sold to third parties, outside of the approved use cases
- Not being used or transferred for purposes that are unrelated to the item's core functionality
- Not being used or transferred to determine creditworthiness or for lending purposes
