GPU-hour
The unit for renting GPU compute: the cost of one GPU for one hour. Obolith normalises every offer to price per GPU-hour so multi-GPU instances can be compared fairly.
What it is
Providers list instances that may bundle 1, 2, 4 or 8 GPUs. To compare them you need instance price / GPU count. An "8x H100 at $22/hr" is $2.75 per GPU-hour; a "1x H100 at $2.40/hr" is cheaper per GPU.
Why it matters
The GPU-hour price is only the sticker. Your real cost per token also depends on generation speed and utilisation - a faster GPU at a higher hourly rate is often cheaper per token.
Cost & infrastructure impact
For the same GPU, on-demand prices vary ~2-3x across specialised clouds, and spot can be another 50-70% cheaper again - with the risk of being reclaimed.