Understand PTUs and billing

A Provisioned Throughput Unit (PTU) is a normalized unit of serving capacity. Every model is priced at the same rate per PTU; what differs per model is how many tokens one PTU can process per minute. When you contract, you decide how many PTUs to reserve based on your traffic.

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Billing

The rate is the same for every model and every workload shape. Within your contracted capacity, you’re billed for the PTUs you reserve, not per token.

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Capacity per PTU

One PTU processes up to the following number of tokens per minute (TPM). Capacity is set per model and per token type: uncached input, cached input, and output. These are each model’s default capacity. A contract can set a different capacity per PTU, and the model page and the Estimate total cost calculator then use the contract’s values.

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Estimate your PTUs and savings

Every model page has an Estimate total cost calculator. Enter your peak requests per second, cache hit rate, and average input and output tokens per request to see how many PTUs you need, the estimated monthly cost, and the estimated savings against a frontier model you pick.

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Example

For example, 8 PTUs on GLM 5.3 Flash give you up to:

• 2,666,664 uncached input tokens per minute, or
• 13,333,336 cached input tokens per minute, or
• 800,000 output tokens per minute.

Real traffic mixes all three, so each type uses a share of the capacity. At $0.05 per PTU per minute, 8 PTUs cost $576 per day. The Estimate total cost calculator counts a month as 730 hours, which puts the same 8 PTUs at about $17,520 per month.

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Traffic above your capacity

The PTUs you reserve set the capacity the SLA guarantees. Traffic above that capacity falls outside the SLA. See Understand the SLA. If you regularly run above capacity, talk to sales to add PTUs.