Bike Stack and Reach Calculator
Enter both points in one coordinate system to calculate their horizontal and vertical separation.
A QUICK WALKTHROUGH
How to use this tool
- Enter the bottom bracket center coordinates.
- Enter the head-tube top center coordinates in the same units and coordinate frame.
- Calculate the coordinate differences.
Coordinate differences
Reach = head-tube-top x − bottom-bracket x. Stack = head-tube-top y − bottom-bracket y. The axes and units must be consistent.
Scope
This reports geometry only. It does not assess rider fit, comfort, posture, or frame suitability.
GOOD TO KNOW
Common questions
Does this tell me which frame to buy?
No. It only subtracts coordinates; frame and rider fit require additional measurements and judgment.