Terms & disclaimer
Estimates, not instructions
Last updated 26 October 2026
A planning aid
Lawn Numbers works out quantities from the numbers you enter and from published university extension formulas. The results are estimates to help you plan and shop. They are not professional advice.
Your label and your local rules come first
Always read and follow the label on the product you use. If the label's rate, timing or warnings differ from anything on this site, the label is right. Some states and towns limit phosphorus or restrict when lawn fertilizer can be applied; check with your local extension office.
No warranty
We work to keep the formulas and ranges accurate and cite our sources, but we cannot promise the site is free of errors or suited to your lawn, climate or product. You use it at your own risk.
Independent
Lawn Numbers is not affiliated with any fertilizer maker or retailer. Product names, if mentioned, belong to their owners.