Map Scale Print Resizing Calculator

Method, example, and limits

Formula: For original scale 1:n and linear resize factor k, new denominator = n/k. A print at p percent has k = p/100.

Inputs and units: n is the original representative-fraction denominator; p is the resized linear dimension as a percent of original. The resulting scale is 1:(n/k).

Worked example: A map at 1:24,000 printed at 80% has a new scale of 1:30,000. A fixed 1 cm paper measurement represents 240 m before resizing and 300 m afterward (125% as much ground distance); the same ground feature's printed length becomes 0.8 cm (80% of its former paper length).

Result meaning: A larger new denominator means each fixed paper unit represents more ground distance after shrinking the map; enlarging reverses that direction. For the same ground feature, the paper length changes by the resize factor.

Assumptions: Resizing is uniform in both page dimensions and the original map scale is a representative fraction. The calculator treats the entered percentage as a linear, not area, scale.

Limits: This does not correct map projection distortion, printer nonuniformity, margins, or a map with a bar scale that is also resized. Verify physical dimensions if scale accuracy matters.