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Corrections, tool requests, embed questions: we read everything.

Things we especially want to hear about:

A wrong number. If a calculator gives a result you can show is incorrect, or cites a study inaccurately, we want to know immediately. We take accuracy reports seriously and fix verified errors quickly.
A tool you wish existed. If there is a size or fit question that deserves an honest, research-backed calculator, tell us about it.
Embedding. Every calculator on this site is free to embed on your own website. If you have a question the embed page does not answer, ask us.

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