Michaelis Menten Kinetics Calculator

Work out michaelis menten kinetics instantly with clear inputs, formula shown and shareable results.

About Michaelis Menten Kinetics Calculator

Applies the Michaelis-Menten equation, in which velocity approaches Vmax hyperbolically and equals half Vmax when substrate equals Km.

Formula

Michaelis-Menten

v = Vmax[S] / (Km + [S]); [S] = Km gives half Vmax and [S] = 9Km gives 90% of Vmax

Worked example

With the default values below, Michaelis Menten Kinetics Calculator returns Reaction velocity of 66.6667. Change any input above and every figure here is recalculated in your browser.

Inputs used

Maximum velocityaccepts 0.001–100,000 micromol/min: 100 micromol/min
Michaelis constantaccepts 0–1,000 mmol/L: 5 mmol/L
Substrate concentrationaccepts 0–10,000 mmol/L: 10 mmol/L

Results

Reaction velocity: 66.6667 micromol/min
Share of maximum velocity: 66.667%
Substrate giving half Vmax: 5.0000 mmol/L
Substrate giving 90% of Vmax: 45.0000 mmol/L

Step by step

1Values used
2Michaelis-Menten
3Reaction velocity= 66.6667 micromol/min
4Share of maximum velocity= 66.667
5Substrate giving half Vmax= 5.0000 mmol/L
6Substrate giving 90% of Vmax= 45.0000 mmol/L

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

What does Km represent?

The substrate concentration giving half-maximal velocity; a low Km means high apparent affinity.

Why is 90 percent saturation costly?

It needs nine times Km, which is why enzymes usually operate well below saturation in cells.