Games Workshop has not released a comprehensive guide to base sizing in Warhammer 40,000. This document presents that here as a means of standardizing base sizes for events.
All base sizes included here are those that are now included with kits as ordered from Games Workshop. However, given that some kits are old inventory, they may be (incorrectly) shipped with the wrong bases.
Most units on Games Workshop are noted as being supplied with a particularly sized base, and instruction booklets also may inform as to the correct diameter.
Kits whose base sizes are in question are appropriately noted as such. Otherwise, please refer to the date on which the base size was last updated if you are concerned about the accuracy of data.
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