System Reference Document

A System Reference Document (SRD) is the base text of the Open Game Content portion of a roleplaying game, and is reproducible under the Open Game License. Although an SRD is ostensibly meant to be only a reference for third parties and not usable as a complete standalone game, most SRDs contain enough of the rules of the game that the game itself is playable using only the SRD. Text from the original source (or related sources) that is explicitly barred from reproduction via the OGL is designated as product identity.

Used generically, the term is usually assumed to refer specifically to the d20 System SRD, specifically the v3.5 revision, unless used in another, more specific context. Other SRDs are usually referenced by name, e.g. the d20 Modern SRD or the Pathfinder SRD.

Unlike most other SRDs (including the ones used in both the 3rd and 5th editions), the Dungeons & Dragons 4th Edition SRD is not published under the OGL, and as such does not allow third-party publishers to reprint the rules of the game. Instead, it serves as an index for third-party publishers wishing to directly reference the 4th Edition rules in their products.

For the text of relevant SRDs, see their respective entries in the wiki.

System Reference Documents

 * d20 System v3.0 SRD, based on Dungeons & Dragons 3rd Edition (out-of-date; see the v3.5 revision below)
 * d20 System v3.5 SRD, based on Dungeons & Dragons v3.5 Edition
 * d20 Modern SRD, based on d20 Modern
 * Dungeons & Dragons 4th Edition SRD, based on Dungeons & Dragons 4th Edition (not a full SRD; see Game System License for more information)
 * Pathfinder Reference Document, based on the Pathfinder Roleplaying Game
 * 13th Age SRD, based on 13th Age
 * Dungeons & Dragons 5th Edition SRD, based on Dungeons & Dragons 5th Edition