Seeds get old, packets get torn, sometimes we forget to jot down the date we harvest them if we seed save. Old seeds don't need to be tossed away though. You can try this simple trick to see if they are still viable and worth planting.
You will need:
Step 1. Wet the paper towel and wring it out until it is damp. Spread it out.
Step 2. Space the seeds evenly along the paper towel.
Step 3. Roll the paper towel up so the seeds are completely covered - they need to stay damp.
Step 4. Put the paper towel somewhere warm (I usually sit it on a sunny windowsill).
Step 5. After two days check to see how many, if any seeds have germinated.
Here's how you can determine the viability:
1 seed germinated = 10% germination rate
5 seeds germinated = 50% germination rate
10 seeds germinated = 100% germination rate
I personally only use the seeds if I get a 50% or more germination rate. You can choose the rate that suits your planting space and harvest needs.