Katal (kat) to Enzyme units Converter

How it is calculated

Both units measure catalytic activity, but with different time and amount bases. One katal is one mole of substrate converted per second; one enzyme unit (U) is one micromole per minute. Since 1 mol = 10⁶ µmol and 1 min = 60 s, the factors are U = kat × 60,000,000 and µkat = kat × 1,000,000. The tool multiplies your katal value by those factors and shows each result to about four significant figures, dropping trailing zeros, so small inputs keep their detail (1.234567×10⁻⁸ kat shows as 0.7407 U). Results of 1,000 or more are shown as whole numbers. Zero and negative inputs are converted as they are, with no warning. Scientific notation such as 2.5e-6 is accepted.

Common mistakes

• Confusing katal with microkatal. Typing a lab value of 5 µkat as 5 kat is a million-fold error; enter 0.000005 kat (or 5e-6) instead.
• Forgetting that the time bases differ (seconds against minutes). Multiplying by 1,000,000 alone gives µkat, not U; the extra factor of 60 is needed for U.
• Entering a negative or zero activity and reading the output as meaningful. The tool converts it without complaint, but a real activity is positive.
• Comparing U with U/L or kat/L. This tool converts activity only; concentration units such as U/L also depend on the sample volume, which you must handle separately.