Calculate percent germination, seeds germinated, or total seeds planted from any two values in a simple seed planting formula for growers.

Percent Germination Calculator

Enter any 2 values to calculate the missing variable

Percent Germination Formula

The percent germination calculator uses the relationship between the number of seeds planted, the number of seeds that germinated, and the germination percentage.

PG = (SG / TS) * 100
SG = TS * (PG / 100)
TS = SG / (PG / 100)
  • PG = percent germination
  • SG = seeds germinated
  • TS = total seeds planted

If you enter total seeds planted and seeds germinated, the calculator finds the percent germination.

If you enter total seeds planted and percent germination, the calculator finds how many seeds germinated.

If you enter seeds germinated and percent germination, the calculator finds the total seeds planted.

Germination Percentage Guide

Use this table as a general way to interpret a germination test result.

Percent Germination General Meaning
90% to 100% Excellent germination. Most seeds are viable.
75% to 89% Good germination. Seed quality is usually acceptable.
50% to 74% Fair germination. You may need to plant extra seeds.
Below 50% Low germination. Seed age, storage, or conditions may be a problem.

Common Germination Test Sizes

Larger test samples usually give a more reliable estimate.

Seeds Tested Best Use Example Result
10 seeds Quick home check 8 germinated = 80%
25 seeds Small seed packet test 20 germinated = 80%
50 seeds More reliable garden test 40 germinated = 80%
100 seeds Easy percentage calculation 80 germinated = 80%

Example Problems

Example 1: Find percent germination

You planted 40 seeds. 34 seeds germinated.

PG = (34 / 40) * 100
PG = 85%

The percent germination is 85%.

Example 2: Find seeds germinated

You planted 120 seeds. The germination rate was 75%.

SG = 120 * (75 / 100)
SG = 90

The number of seeds germinated is 90.

FAQ

What does percent germination mean?

Percent germination is the percentage of planted or tested seeds that successfully sprout. For example, if 45 out of 50 seeds germinate, the germination percentage is 90%.

Can percent germination be over 100%?

No. Percent germination cannot be greater than 100% because the number of germinated seeds cannot be greater than the total number of seeds planted.

Why is my germination percentage low?

Low germination can happen because of old seeds, poor seed storage, too much or too little water, incorrect temperature, poor soil contact, or planting too deeply. A germination test helps you decide if you should plant extra seeds or replace the seed lot.