How do I estimate my model surface area?

For a rough estimate, measure the length, width and height of the model and calculate the surface area as if it were a rectangular box. For aircraft, the wing area plus fuselage cylinder area gives a reasonable estimate. A 1:72 fighter typically has 150-300 cm² of paintable surface.

How many coats do I need?

Most model paints need 2-3 thin coats for full coverage. Light colours over dark primers may need 3-4 coats. Primer itself usually needs 1-2 coats. Always apply thin coats rather than one thick coat.

How much does a spray can cover?

A standard 100ml Tamiya spray can covers approximately 0.5-1 m² (5,000-10,000 cm²) depending on coat thickness. That is enough for several 1:72 or 1:48 models.

ModelCalcs

Spray Coverage Calculator — Paint Quantity Estimator

Estimate how much spray paint, airbrush paint or brush paint you need based on model surface area and coat count.

Surface Area

Approximate paintable surface area

Number of Coats

Application Method

Can/Bottle Size

Price per Can/Bottle (optional)

How We Calculate This

Paint volume = Surface area × Coverage rate × Number of coats. Airbrush is most efficient at approximately 1ml per 100cm². Spray cans use about 50% more due to overspray. Brush painting falls between the two.

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates. Always verify quantities before purchasing materials.