Does base size matter in competitive play?

Yes, in most competitive game systems the official base size affects movement ranges, line of sight, and model footprint. Using incorrect bases can give unfair advantages. Always check current rules — GW has changed base sizes for several units over the years.

Can I use different base shapes?

Most game systems now specify round or oval bases. Square bases are still used in Kings of War and some rank-and-flank games. In casual play, most opponents will not mind as long as the base area is similar. For tournaments, use the officially specified bases.

Where can I buy bases separately?

Games Workshop sells base sets. Third-party suppliers like Renedra, Warbases (UK), and Sarissa Precision offer bases in all standard sizes at lower cost. Warbases also makes custom shapes and sizes. MDF bases from laser-cut suppliers are cheapest.

What if GW has changed the base size for my unit?

Games Workshop occasionally updates base sizes when ranges are refreshed. The current official recommendation is shown on the product page. If you have older models on smaller bases, you can rebase them or use base adapters (rings that fit around the old base).

ModelCalcs

Base Size Calculator — Correct Miniature Bases

Look up correct base sizes for miniature figures by game system and unit type.

Game SystemChoose the ruleset whose official base sizes you want (40k, AoS, Bolt Action, Kings of War).

Unit TypePick the model role (infantry, cavalry, monster, vehicle) to look up its official base.

How We Calculate This

Looks up the official base size for your chosen game system and unit role from a verified table (Games Workshop 40k/AoS, Warlord Bolt Action, Mantic Kings of War), then reports the base shape, footprint area and a basing cost.

Footprint area is computed from both base axes, not a single diameter: round bases use π·r², oval bases use π·(major/2)·(minor/2), and square/rectangular bases use width × height. A 75×42mm oval is therefore ≈ 2,474 mm², not 5,625 mm².

Common Warhammer 40k base sizes

25mm round — Standard infantry (Guardsmen, Tactical Marines)
32mm round — Large infantry (Primaris, Gravis armour)
40mm round — Heavy infantry and many characters (Terminators, Ogryn)
60mm round — Dreadnoughts, medium monsters
75×42mm oval — Bikes and cavalry

Frequently Asked Questions

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Last updated: February 2026

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