What is Cloud HD?
An optional Pro mode that runs a larger model in the cloud: up to 8x and 64 MP for images, video up to 4K, batches of up to 50. It uses credits.
Cloud HD is for the work a browser cannot do: images up to 8x and 64 MP of output, video up to 4K, batches of up to 50 files, several jobs at once. The file you pick for it is uploaded for that job and the result is saved to your library.
Cloud HD is part of Pro and uses credits. Pro includes a weekly or monthly credit grant, and credit packs top it up. An HD image costs 10 credits per 16 MP of output; video costs 10 credits per second at 1080p and 40 per second at 4K, doubled above 30 frames per second. Megapixels and seconds are rounded up to the next billing unit.
The signed-out free tool uploads nothing. Signing in saves finished results to your library; Cloud HD uploads the file you choose for that job.