About FormuSolve

FormuSolve makes free, practical calculators that answer your numbers. Most online "calculators" hand you a one-size chart and leave you to do the math; ours take your actual inputs — your pool's gallons, your zip codes, your kid's height — and give you the specific answer for your situation.

Each tool is built by someone who actually needed it, and we're honest about what the tools can and can't do (see our disclaimer). Doses and estimates lean conservative on purpose, and every result tells you how to double-check it.

How we're funded

FormuSolve is free to use. Some pages include affiliate links to products relevant to your result — if you buy through one, we may earn a small commission at no extra cost to you. That never changes the calculation or the recommendation; the math comes first.

Contact

Questions, corrections, or a calculator you wish existed? Reach us at [email protected].