You can get a default sized (128x128) emblem from https://emblem.werdes.net/emblem/{guild-id}
Requesting an emblem for a non-existing guild or a guild without an emblem will result in a default image (Example) and a "NotFound"-Information in Headers (see "Headers")
Example: https://emblem.werdes.net/emblem/0442B0AE-23BF-E711-81A1-020CAB02238C
You can resize the emblem by adding the size as an additonal parameter behind the guild-id.
Note: Minimum size is 1x1, maximum size is 512x512
Example: https://emblem.werdes.net/emblem/0442B0AE-23BF-E711-81A1-020CAB02238C/64 will result in a 64x64 version of that emblem.
You can manipulate the emblem in certain ways by adding the ?options= parameter at the end.
MaximizeAlpha
Theres currently BackgroundMaximizeAlpha and ForegroundMaximizeAlpha available, which will scale the alpha of the corresponding part of the emblem up to 1 so it looks less washed on light backgrounds. You can combine options by seperating them with a comma (,). Compare the background of the following two emblems:
Individual emblems are cached for 24 hours to reduce API calls.
The Response (if successfully served) will contain a Emblem-Status header that will tell you wether the emblem is OK or NotFound.