Michaelis-Menten Enzyme Kinetics Calculator
Calculate enzyme reaction velocity using Michaelis-Menten kinetics.
Find Km and Vmax from data points using Lineweaver-Burk double reciprocal analysis.
Michaelis-Menten Equation Describes how reaction velocity V depends on substrate concentration [S].
V = Vmax × [S] / (Km + [S])
Where:
- Vmax = maximum reaction velocity (when all enzyme is saturated)
- Km = Michaelis constant — the substrate concentration at which V = Vmax/2
- [S] = substrate concentration
Km Significance A low Km means the enzyme reaches half-maximum rate at very little substrate — high affinity. A high Km means more substrate is needed — lower affinity.
Catalytic Efficiency kcat/Km (specificity constant) — but since kcat requires enzyme concentration, we use Vmax/Km as a relative efficiency measure.
Lineweaver-Burk Plot (double reciprocal) Rearranging gives a straight line: 1/V = (Km/Vmax) × (1/[S]) + 1/Vmax
- y-intercept = 1/Vmax
- x-intercept = −1/Km
- slope = Km/Vmax
Enter 2 or 3 data points ([S], V) and the calculator finds Km and Vmax using linear regression on the reciprocals.