Plans and Included Hours
Cells usage is measured in Small-hours: one Small-hour equals one hour of continuous small-size session time. Each plan includes a monthly allowance of Small-hours. Larger session sizes consume more Small-hours per wall-clock hour.
Plans
| Plan | Price / month | Small-hours / month | Concurrent sessions | Warm Python slots | Storage included |
|---|---|---|---|---|---|
| Free | $0 | 10 (hard stop) | 2 | 0 | 2 GB |
| Starter | $29 | 250 | 5 | 1 | 10 GB |
| Growth | $99 | 1,000 | 20 | 10 | 50 GB |
| Scale | $299 | 4,000 | 100 | 20 | 100 GB |
micro size only; all other languages and sizes cold-start (about 12 seconds at p50).micro and small sizes and has no warm pool. The 10 Small-hours/month limit is a hard stop: session creation returns 402 SMALL_HOURS_EXHAUSTED once the allowance is exhausted, and it does not roll over.Small-hours explained
A "Small-hour" is defined as one hour of a small-size session (1 vCPU, 2 GB RAM). Other sizes have a multiplier applied:
| sizeId | Multiplier | Small-hours per hour |
|---|---|---|
micro | 0.53x | 0.53 |
small | 1.0x (reference) | 1.0 |
standard | 2.0x | 2.0 |
large | 4.0x | 4.0 |
max | 8.0x | 8.0 |
Sessions are metered from start to end (or timeout). If a session runs for 10 minutes using a standard size, it consumes (10/60) * 2.0 = 0.33 Small-hours from your monthly balance.
Concurrent session limit
Each plan sets a maximum number of concurrently running sessions per organization. Attempts to create a session when the limit is reached return a 429 response with error code CONCURRENT_LIMIT_REACHED.
alwaysOn sessions
Always-on sessions require a Growth or Scale plan. They persist indefinitely rather than timing out, are billed at a flat monthly rate per slot, and do not consume Small-hours. The per-org concurrent always-on limit is enforced separately from the regular concurrent session limit.
Quota exhaustion (402)
When the monthly Small-hours allowance is exhausted, session creation returns 402 Payment Required with error code SMALL_HOURS_EXHAUSTED. The session is not created. Upgrade to a higher plan or wait for the next billing cycle to restore the allowance.