A seed value is a number that relates to the starting point of the AI image or video generation process inside the model. For example, if you generate an image or video with the same prompt twice the two images will likely be very different because a new seed is used each time.
If you generate an image or video and like it, and want to generate a very similar image that's slightly different, you might change your prompt and input the seed value from the previous image or video. This will result in a very similar image or video but with the changes in the prompt.
To view and copy the seed from a particular image or video, click the three dots in the top right corner of the image and select 'View Provenance':
You can copy the seed from the image or video you like here and then paste it beneath the prompt in 'Generate Options'
Note: Currently seed values are only populated when you generate one image or video at a time, and they are only supported by the following models:
Imagen
Stable Diffusion
Stable Diffusion 3
Bria Images
Adobe Firefly
Veo 2