BUILD IT / BASE PLANNING
Base Size & Rebase Planner
Enter your measured current and target base sizes. Compare centered, unrotated footprints and estimate your own replacement-base costs. No official game sizes or rules are supplied.
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LIVE CALCULATORPrint a measured size guide
Download an A4 SVG with both outlines and a 100 mm calibration line. Print at actual size / 100%, disable fit-to-page, and measure the line with a ruler. First use 100 for the measured-line input; enter that uncorrected print’s measurement to make a corrected sheet. Requested and compensated outlines must both fit within the 180 mm drawing area. This is a flat size guide, not an adapter design.
The math behind Base Size & Rebase Planner
Formula and units
Circle area = π × diameter² / 4; oval area = π × width × length / 4; rectangle area = width × length; square area = width². Area change = (target area / current area − 1) × 100%. Required bases = model count plus spare allowance rounded upward; buy whole packs. Print correction = 100 / measured length of the uncorrected 100 mm line.
Worked example: 3 base packs
Twenty miniatures with 10% spares need 22 target bases. Packs of ten require three packs: 30 purchased, eight beyond the requested 22. At $5 per pack plus $2 supplies, the estimate is $17. Moving from 25 mm to 32 mm circles increases area from about 4.91 to 8.04 cm², or 63.84%, and the smaller circle fits centered inside the larger outline.
Common mistakes
Use the measured outside dimensions of the existing and proposed bases. A rectangle can have less area than a circle and still fail to fit because its corners extend beyond the circle. The fit check uses the entered orientation, without rotating a base. A flat template does not account for a base lip or height.
Does this choose the correct tournament base size?
No. You choose every size. Check the applicable event or publisher requirements independently; this tool does not reproduce official unit tables or determine game legality.
How do I print a true-size guide?
Download the A4 SVG, open it in a viewer that preserves physical units, and print at actual size / 100% with fit-to-page disabled. Measure its 100 mm reference line. Starting from an uncorrected sheet with the measurement set to 100, enter the measured line length to compensate and download again. Recheck the corrected print with a ruler.
Can I make an adapter from this outline?
The sheet is a size comparison guide, not an engineered adapter or cutting pattern. Check physical tolerances and the actual assembly before modifying or attaching a miniature.
Why is the template download limited?
The requested and corrected current and target outlines must each fit within the 180 mm A4 drawing area. Larger bases still calculate, but need another physical measuring method.