Free home project calculator

Free grass seed calculator

The grass seed calculator estimates how much seed you may need based on area and the coverage rate from the bag. Use it for overseeding, patch repair, or planning a new lawn area.

Open this calculator

When to use this calculator

  • Overseeding existing lawn
  • Repairing bare patches
  • Planning a new lawn
  • Estimating seed bag counts

Tips for a better estimate

  • Use the coverage rate printed on the seed bag.
  • New lawn and overseeding rates are often different.
  • Prepare soil before spreading seed.
  • Keep the seedbed consistently moist while germinating.
HomeCalc gives planning estimates only. Product labels, package sizes, coverage rates, supplier conversions, local code, and site conditions can change the final quantity you need.

Frequently asked questions

Why do seed bags show different coverage rates?

Coverage depends on seed type and whether you are overseeding or starting a new lawn.

Can I use metric measurements?

Yes. HomeCalc supports feet/inches and metric inputs.

Should I buy extra seed?

A small buffer can help with thin areas, edges, and uneven spreading.