Lawn Seed Calculator
Fill in the values and the answer updates as you type.
How the Lawn Seed Calculator works
Seed (kg) = area × seeding rate ÷ 1,000. New lawns usually use 30–50 g/m², while overseeding an existing lawn needs about half of that. Cost is based on the exact weight, not the full bags. Example: with the default values, a 100 m² lawn at 35 g/m² needs 3.5 kg of seed.
Inputs and results
The Lawn Seed Calculator takes 4 inputs and gives 3 results.
What you enter
- Lawn area (m²) — starts at 100.
- Seeding rate (g/m²) — starts at 35.
- Bag size (kg) — starts at 5.
- Price per kg ($) — starts at 12.
What you get
- Seed needed (kg)
- Bags needed
- Estimated seed cost
Example: Lawn Seed Calculator with the starting values
With lawn area 100 m², seeding rate 35 g/m², bag size 5 kg and price per kg 12 $, the calculator returns:
| Seed needed (kg) | 3.5 |
|---|---|
| Bags needed | 1 |
| Estimated seed cost | $42 |
Change any value above and the results update straight away.
Lawn Seed Calculator FAQ
How do I use the Lawn Seed Calculator?
Enter lawn area, seeding rate, bag size and price per kg in the fields, then read seed needed (kg), bags needed and estimated seed cost in the result panel. The answer updates as you type, and you can press Calculate or Enter to refresh it. Use “Copy link” to share your exact numbers with someone else.
What does the Lawn Seed Calculator calculate?
How much grass seed you need for a new or overseeded lawn. It returns seed needed (kg), bags needed and estimated seed cost from the 4 values you provide.
What values does the Lawn Seed Calculator start with?
It opens with lawn area 100 m², seeding rate 35 g/m², bag size 5 kg and price per kg 12 $ so you can see a working result straight away. Replace them with your own numbers, or press Reset to return to these starting values.
Is the Lawn Seed Calculator free and private?
Yes. It is free, needs no account, and runs in your browser, so nothing you type is sent to or stored on our servers. See the Privacy Policy for details.
Can I rely on the Lawn Seed Calculator for important decisions?
Treat the result as a well-rounded estimate. Real situations often have details a general calculator cannot know, so confirm important decisions with a qualified professional. See the Disclaimer for more.