How do I calculate how much fertilizer to apply to my lawn?

Divide your lawn area by 1,000, multiply by your desired nitrogen rate in lbs per 1,000 sq ft, then divide by the bag nitrogen percentage as a decimal. Example: 5,000 sq ft at 1.0 lb N rate with a 32% N bag = (5,000 / 1,000) x 1.0 / 0.32 = 15.6 lbs of product.

What is a typical nitrogen rate for a lawn?

Most cool-season grasses (fescue, Kentucky bluegrass) perform well at 0.5 to 1.0 lbs of nitrogen per 1,000 sq ft per application. Warm-season grasses (bermuda, zoysia) can handle up to 1.5 lbs. Never exceed 1.5 lbs N per 1,000 sq ft per application to prevent fertilizer burn.

Where do I find the nitrogen percentage on a fertilizer bag?

The nitrogen percentage is the first number in the three-number analysis printed on every fertilizer bag. A bag labeled 32-0-10 contains 32% nitrogen, 0% phosphorus, and 10% potassium. Enter that first number into this calculator.

🌱 Nitrogen Rate Calculator

Exactly How Much Nitrogen Your Lawn Needs

Calculate precisely how much fertilizer to apply based on your lawn size, desired N rate, and bag N%.

Jump to Calculator ↓

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Calculate Your Nitrogen Application

Enter your lawn details to find out how much product to buy and apply.

Lawn Area (sq ft)

Desired N Rate (lbs / 1,000 sq ft)

Fertilizer N% (from bag label)

Output Unit

💡 The N% is the first number in the fertilizer analysis (e.g. a 32-0-10 bag is 32% nitrogen). Typical lawn N rates are 0.5–1.5 lbs per 1,000 sq ft per application.

Fertilizer to Apply

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⚠️ Always water in fertilizer after application. Follow label rates to avoid burn. Do not apply before rain is forecast.

Lawn Care 101

Not Sure What the Numbers on the Bag Mean?

The three numbers on every fertilizer bag — N-P-K — tell you exactly what's inside. Read the guide to understand why the first number is all that matters for most lawns, and how to use it to shop smarter.

Read the N-P-K Guide →

NNitrogen

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PPhosphorus

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KPotassium

Gear & Tips

What You'll Need

My Fertilizer Pick

Top Pick

Anderson's CORE 12-8-12 All-Season Lawn Fertilizer

“The fertilizer I reach for when I want fast results. The nitrogen comes from Ammonium Sulfate — it's quick-release, lowers soil pH, and you'll see green in days, not weeks.”

Professional-grade 12-8-12 formula — balanced N-P-K for all-season feeding
Nitrogen from Ammonium Sulfate — fast-acting, greens up your lawn within days of watering in
Slightly acidic — helps lower soil pH over time, which most cool-season grasses prefer
Includes micronutrients + 2% iron for deeper, richer green color
Ultra-fine particle size — 60% smaller than standard consumer granules for more even, complete coverage
Feeds for up to 6 weeks — can be reapplied every 4–6 weeks during the growing season
Available in 5,000 sq ft and 12,500 sq ft bags

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My Spreader Pick

Top Pick

ECHO RB-60 Heavy-Duty Broadcast Spreader

“The spreader I use on my own lawn — nothing else comes close.”

60 lb hopper — covers up to 25,000 sq ft per load
Factory-calibrated spread pattern up to 8 ft wide
Maintenance-free gear case — no grease, no hassle
Foot-operated side deflector keeps product off driveways & beds
10" pneumatic tires handle any terrain with ease
Powder-coated steel frame — 5-year consumer warranty

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When to Fertilize

Cool-season grasses (fescue, bluegrass) do best with fall applications. Warm-season grasses (bermuda, zoysia) respond well to late spring and summer feeding. Avoid fertilizing drought-stressed lawns.