Quick formula
Pounds of product per 1,000 sq ft = target pounds of nitrogen ÷ nitrogen percentage as a decimal.
Example: if your target is 0.5 lb N per 1,000 sq ft and the fertilizer is 16% nitrogen, calculate 0.5 ÷ 0.16 = 3.125 lb of product per 1,000 sq ft.
Common examples
- 0.5 lb N with 16-4-8: 0.5 ÷ 0.16 = 3.1 lb product per 1,000 sq ft.
- 0.5 lb N with 29-0-5: 0.5 ÷ 0.29 = 1.7 lb product per 1,000 sq ft.
- 0.5 lb N with 46-0-0 urea: 0.5 ÷ 0.46 = 1.1 lb product per 1,000 sq ft.
- 1.0 lb N with 10-0-1 organic: 1.0 ÷ 0.10 = 10 lb product per 1,000 sq ft.
Scale it to your actual lawn
Once you know pounds per 1,000 sq ft, multiply by your treated area divided by 1,000. If the rate is 3.1 lb per 1,000 and your front yard is 4,200 sq ft, you need 3.1 × 4.2 = 13.0 lb of product.
If you do not know your treated area, start with the free lawn measurement tool.
Do not confuse bag coverage with your target rate
Bag coverage can be useful, but it may assume a specific nitrogen delivery rate or marketing pattern. If you are trying to hit a controlled nitrogen target, use the N-P-K percentage and your actual square footage. Then compare that result with the label directions and local restrictions.
Why logging matters
Fertilizer math only helps if you remember what went down. Log product, rate, area, nitrogen delivered, weather, and response. That prevents accidental over-application and helps you learn which products actually fit your lawn.
Use Lawn Dominator
Use the free fertilizer calculator for the math, the Price Board to compare product prices, and the app to track nitrogen by lawn section over the last 30 days.