Granular products are common for lawns; liquids act faster. Always follow label application rates.

Lawn Fertilizer NPK Calculator - Per 1,000 ft²

Q: What target N should I use?

Typical single application is 0.5–1.0 lb N per 1,000 ft² (0.25–0.5 kg N per 100 m²). Follow label and local guidelines.

Q: What do the P and K numbers mean?

N is nitrogen, P is phosphate (P₂O₅), and K is potash (K₂O), each as weight percentages in the fertilizer grade.

Q: How many applications per year?

Often 2–4 depending on grass type and climate. Split doses for safety and efficiency.

Q: Can I over-fertilize?

Yes. Over-application can burn turf and cause runoff. Do not exceed labeled rates and water-in if required.

Dial in your fertilizer like a pro. Set lawn size, target N per 1,000 ft² (or per 100 m²), your fertilizer grade (N-P-K), and bag weight. Get how much to apply, bags needed, and nutrient totals—with optional cost.

🌿 Lawn Fertilizer N-P-K Calculator

How much fertilizer to apply per application for any N-P-K grade—plus bags and nutrient totals.

Results

Tip: Many cool-season lawns max at 0.75–1.0 lb N/1,000 ft² per application. Always follow label.

How to Use the N-P-K Calculator

Choose Units and enter Lawn Area.
Set Target N per 1,000 ft² (or per 100 m²).
Enter your product’s N-P-K grade (e.g., 16-4-8) and bag weight.
Click Calculate → get product weight, bags, and nutrient totals.

Fertilizer FAQ

What target N should I use?

Typical single application: 0.5–1.0 lb N/1,000 ft² (0.25–0.5 kg N/100 m²). Follow label & local guidelines.

What do the P and K numbers mean?

N = Nitrogen, P = Phosphate (P₂O₅), K = Potash (K₂O), by weight %. The tool reports applied totals.

How many applications per year?

Commonly 2–4, depending on grass type and climate. Split into smaller doses for safety.

Liquid vs granular?

Granular is common for lawns; liquids are fast-acting. Always follow the product label rate.

Can I over-fertilize?

Yes—risk of burn and runoff. Never exceed label rates. Water-in if required.