Reference
Heat ledger
The public monthly record of every GPU hour in a forge.
On the second business day of each month we publish a ledger for each forge. It is built from the heat feed and the billing records, and it is where every number on our site comes from.
What it contains
- GPU hours available: GPUs times hours in the month, minus announced maintenance.
- Hours by plan: Anvil, Strike, Hour bank, Ember, and cold hours when nothing ran.
- Load: mean utilisation over all hours, and over hours with a job running.
- Uptime: with every down minute listed and its cause.
- Waits: median and 95th percentile queue time for Strike and Ember.
- Ember runs: median time an Ember job ran before preemption.
- Price check: our rates next to the list price of a comparable B200 instance at the four largest clouds on the 1st of the month. We do not name them.
- Next forge: each commissioning step, done or open.
- Price notice: any change taking effect next month.
Example, September 2026
| Line | Value |
|---|---|
| GPU hours available | 11,488 |
| Anvil | 5,760 |
| Strike | 2,214 |
| Hour bank | 1,906 |
| Ember | 1,071 |
| Cold | 537 |
| Load, all hours | 86.2 % |
| Load, busy hours | 90.4 % |
| Uptime | 99.97 %, 13 min down |
| Strike wait, median and p95 | 1 min, 18 min |
| Ember run before preemption, median | 3 h 40 min |
Reading it with the API
curl https://api.useblackforge.com/v1/ledger/2026-09?forge=f1 -H "Authorization: Bearer $BF_KEY"The JSON has every line above, plus a per day breakdown and the list of down minutes.
Why publish it
A price only means something next to what it bought. If the forge gets fuller, the queues get longer or downtime creeps up, you will see it here before you feel it.