Measure twice, make once
Round-hoop fit planner
Find the minimum inner diameter that contains a rectangular design and clearance.
The page shows its formula, example, assumptions, rounding, and limitations beside the calculator.
Round-hoop fit planner
Find the minimum inner diameter that contains a rectangular design and clearance.
Formula and assumptions
The mathematical minimum inner diameter is the diagonal of the design rectangle after clearance is added on every side. The practical suggestion rounds up to a common 3, 4, 5, 6, 7, 8, 10, or 12 inch hoop; verify the actual inner opening and choose a frame when that diameter is impractical.
Worked example
Example: an 8 × 6 cm design with 1 cm clearance needs at least a 12.81 cm inner diameter.
Limits and rounding
Results are planning estimates from the values entered. Displayed decimals are rounded for craft use; whole materials and repeats round up where the method says so. Confirm gauge, material behavior, construction, and finished measurements before committing supplies.