Altitude Baking Adjustment Calculator

Adjustments typically become necessary above 900 metres (3,000 feet). At these altitudes, lower air pressure causes cakes to rise faster, lose moisture more quickly, and structure differently. The higher the altitude, the more pronounced the effects.

At high altitude, lower air pressure means gases in the batter expand more quickly and the cake rises too fast before the structure has set. The result is often a cake that rises dramatically and then collapses in the centre. Reducing leavening and increasing structure (flour) helps counter this.

Bread is generally less affected than cakes because the gluten structure is stronger. However, dough rises faster at altitude, so reduce the rising time or use slightly less yeast. You may also need a little extra liquid as dough dries out more quickly.

Yes. Water boils at a lower temperature at high altitude (roughly 1°C lower per 300m), and ovens may behave slightly differently. Raising the oven temperature by 15-25°F (about 8-14°C) helps the cake structure set before over-rising occurs. This calculator applies a +14°C bump (≈ +25°F, the top of that range); baking authorities such as Wilton and King Arthur cap the increase at 15-25°F regardless of how high you go, so it does not keep rising with altitude.