Convert 1 square kilometer to square millimeter

1 km² (square kilometer) is equal to 1,000,000,000,000 mm² (square millimeter). To convert from square kilometer to square millimeter, multiply by 1,000,000,000,000 or divide by 0.000000000001.

• 1 km² × 1000000000000 = 1000000000000 mm²
• 1 km² ÷ 1.0E-12 = 1000000000000 mm²