Square Inches to Square Nanometers: the quick answer
1 in² = 645,160,000,000,000 nm²
1 square inch equals 645,160,000,000,000 square nanometers
To convert square inches to square nanometers, multiply the value by 645,160,000,000,000. To go the other way, multiply square nanometers by 1.55 × 10⁻¹⁵ to get square inches.