Provisioned Throughput Units (PTU) Guide
Table of Contents: Understanding PTU vs Standard TPM · When to Use PTU · PTU Capacity Planning · Deploy Model with PTU · Request PTU Quota Increase · Understanding Region and Deployment Quotas · External Resources
Understanding PTU vs Standard TPM
Microsoft Foundry offers two quota types:
Standard TPM (Tokens Per Minute)
- Pay-as-you-go model, charged per token
- Each deployment consumes capacity units (e.g., 10K TPM, 50K TPM)
- Total regional quota shared across all deployments
- Subject to rate limiting during high demand (429 errors possible)
- Best for: Variable workloads, development, testing, bursty traffic
Provisioned Throughput Units (PTU)
- Monthly commitment for guaranteed throughput
- No rate limiting, consistent latency
- Measured in PTU units (not TPM)
- Best for: Predictable, high-volume production workloads
- More cost-effective when consistent token usage justifies monthly commitment
When to Use PTU
| Factor | Standard (TPM) | Provisioned (PTU) |
|---|---|---|
| Best For | Variable workloads, development, testing | Predictable production workloads |
| Pricing | Pay-per-token | Monthly commitment (hourly rate per PTU) |
| Rate Limits | Yes (429 errors possible) | No (guaranteed throughput) |
| Latency | Variable | Consistent |
| Cost Decision | Lower upfront commitment | More economical for consistent, high-volume usage |
| Flexibility | Scale up/down instantly | Requires planning and commitment |
| Use Case | Prototyping, bursty traffic | Production apps, high-volume APIs |
Use PTU when:
- Consistent, predictable token usage where monthly commitment is cost-effective
- Need guaranteed throughput (no 429 rate limit errors)
- Require consistent latency with performance SLA
- High-volume production workloads with stable traffic patterns
Decision Guidance: Compare your current pay-as-you-go costs with PTU pricing. PTU may be more economical when consistent usage justifies the monthly commitment.
PTU Capacity Planning
Official Calculation Methods
Agent Instruction: Only present official Azure capacity calculator methods below. Do NOT generate or suggest estimated PTU formulas, TPM-per-PTU conversion tables, or reference deprecated calculators (oai.azure.com/portal/calculator).
Calculate PTU requirements using these official methods:
Method 1: Microsoft Foundry Portal
- Navigate to Microsoft Foundry portal
- Go to Operate → Quota
- Select Provisioned throughput unit tab
- Click Capacity calculator button
- Enter workload parameters (model, tokens/call, RPM, latency target)
- Calculator returns exact PTU count needed
Method 2: Using Azure REST API
# Calculate required PTU capacity