Put a few in water for a few days. Maybe a week. If they sprout, they're viable. In fact, when they sprout, you can go ahead and plant them in soil. If you want to test viability, test viability.

The float "test" helps when cleaning seeds that have recently been removed from the pumpkin. Once seeds have been dried out for storage you can check germination by planting them or placing them on a moist paper towel placed in a plastic bag and kept in a warm place.

YEP they should grow, squash seeds from last fall came up, watermelon too! as long as they are stored room temperature.

They have too much surface area to test by floating accurately. Just see if they sprout in water