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?

These are rough estimates — actual coverage swings widely with thinning, air pressure, spray distance and coat thickness. As a guide, a standard 100ml Tamiya TS spray can is enough to fully paint about 2-3 1:24 car bodies, or roughly 0.5-1 m² (5,000-10,000 cm²). That stretches to several 1:72 or 1:48 models. Treat the result as a starting point and round up so you do not run dry mid-coat.

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

Paintable surface area. Rough box estimate is fine: a 1:72 fighter is ~150-300 cm²

Number of Coats

Thin coats to apply: most paints need 2-3; light over dark primer 3-4

Application Method

Can/Bottle Size

Volume per can or bottle: Tamiya TS can 100ml, acrylic dropper bottle ~17-23ml

Price per Can/Bottle (optional)

Cost in your local currency

How We Calculate This

Paint volume = Surface area × Coverage rate × Number of coats. The default coverage rates are approximate and will vary with thinning ratio, technique and coat thickness. Airbrushing is most efficient at roughly 1ml per 100cm² (0.01 ml/cm²); rattle cans use about 50% more (0.015 ml/cm²) because of overspray; brush painting (0.012 ml/cm²) falls between the two. Override any rate under Advanced Options if you have measured your own usage. The benchmark behind these figures: one 100ml Tamiya TS can covers ~2-3 1:24 car bodies.

Frequently Asked Questions

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Last updated: February 2026

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