Compare API cost with the workload in mind
A useful API price page should explain how to compare models, token mix, retries, tools, and limits. This guide points to live values instead of making a fragile permanent «cheapest API» promise.
Current prices of flagship models
Prices checked from the live catalog. "From" is the lowest price among the relay.fast sources that currently serve the model. The price you pay depends on the source your request uses and can change on any day. The pricing page always shows current values.
| Model | Model ID | Official input / output per 1M tokens | relay.fast from, input / output | Cache read from | Context |
|---|---|---|---|---|---|
| Claude Opus 5.5 | claude-opus-5-5 | $4 / $20 | $0.111 / $0.556 (−97%) | $0.00556 | 1M |
| Claude Sonnet 5.5 | claude-sonnet-5-5 | $2 / $10 | $0.238 / $1.19 (−88%) | $0.0238 | 1M |
| Claude Haiku 5.5 requests above 100K input tokens cost more | claude-haiku-5-5 | $0.1 / $0.5 | $0.0223 / $0.112 (−77%) | $0.00223 | 1M |
| GPT-6.1 Sol requests above 272K input tokens cost more | gpt-6.1-sol | $2 / $10 | $0.03 / $0.15 (−98%) | $0.0015 | 1.05M |
| GPT-6 Astra requests above 272K input tokens cost more | gpt-6-astra | $10 / $50 | $0.1 / $0.5 (−99%) | $0.01 | 1.05M |
| GPT-6 Luna requests above 272K input tokens cost more | gpt-6-luna | $0.1 / $0.5 | $0.008 / $0.04 (−92%) | $0.0008 | 1.05M |
| Gemini 4 Argon | gemini-4-argon | $4 / $20 | $0.32 / $1.6 (−92%) | $0.016 | 1.05M |
| Gemini 3.8 Flash | gemini-3.8-flash | $1.5 / $7.5 | $0.06 / $0.3 (−96%) | $0.006 | 1.05M |
| Grok 4.7 requests above 200K input tokens cost more | grok-4.7 | $2 / $6 | $0.0133 / $0.04 (−99%) | $0.00333 | 500K |
| DeepSeek V4.1 Flash price depends on the time of day; the peak-hours price is shown | deepseek-v4.1-flash | $0.3 / $1.2 | $0.03 / $0.12 (−90%) | $0.0006 | 1M |
| GLM-5.3 | glm-5.3 | $1.4 / $4.4 | $0.035 / $0.11 (−97%) | $0.0065 | 1M |
| Kimi K3 | kimi-k3 | $3 / $15 | $0.15 / $0.75 (−95%) | $0.015 | 1.05M |
| Qwen3.8 Max | qwen3.8-max | $2 / $6 | $0.0667 / $0.2 (−96%) | $0.00833 | 1M |
| MiniMax M3 | minimax-m3 | $0.3 / $1.2 | $0.05 / $0.2 (−83%) | $0.01 | 1M |
What changes your bill
- Input and output tokens, including long context and tool results.
- Model family, capability tier, and any provider-specific multiplier.
- Retries, streaming interruptions, image or audio inputs, and background jobs.
- Minimums, rate limits, account balance rules, and taxes or payment fees where applicable.
A fair GPT versus Claude test
Choose a fixed prompt set from your real application, freeze the model versions, run enough requests to smooth latency variance, and record successful completion rate, p50/p95 latency, input/output tokens, and total spend. Publish the date and methodology when making a public comparison.
Where to check current values
Use live pricing catalog for the live model catalog, interactive setup docs for request examples, and service status for incidents. If you need a security or retention answer before purchase, read security overview and the data-retention page.
Frequently asked questions
Does relay.fast always have the lowest price?
No permanent claim is made. Compare the current catalog with your workload, reliability needs, and the total cost of retries and operational time.
Is there a free API key?
The service uses account-based credentials. Check the current signup and billing terms rather than relying on shared or unofficial keys.
How are tokens counted?
Usage is reported by the API response and account dashboard. Validate the exact model and response fields used by your client.