Square root of 45

√45 ≈ 6.7082

√45 is an irrational number, so its decimals never end or repeat. It sits between 6 and 7 because 6² = 36 and 7² = 49.

√45 rounded

Simplest radical form

45 = 9 × 5 and √9 = 3, so √45 = 3√5.

Check the answer

6.7082 × 6.7082 ≈ 44.9999, which is very close to 45.

Need another number? Use the square root calculator (also cube roots and other roots).

Square roots near 45

All square root answers · Exponent calculator