Cheapest GPT-5 Pro API: RunAPI is 94% below the official price
GPT-5 Pro costs $15.00/$120.00 per 1M tokens from OpenAI. The lowest quote in the index is RunAPI: $0.900 in, $7.20 out. Full table and buying checklist below.
| # | Provider | 1M input | 1M output | vs list | Tokens per $100 |
|---|---|---|---|---|---|
| — | Official list | $15.00 | $120.00 | 0% | 3.08M |
| 1 | $0.900 | $7.20 | −94% | 51.3M | |
| 2 | $2.25 | $18.00 | −85% | 20.5M | |
| 3 | $22.05 | $176.42 | +47% | 2.09M |
Scroll the table sideways to see every price.
Tokens per $100 assume a “code” mix: 5 input tokens per output token. Prices are crawled; verify them on the provider page before buying.
What to check before buying
- Test the key with the free API checker — it verifies the endpoint responds, without sending tokens.
- Compare the blended cost for your workload, not just the input price: output tokens dominate in agent workloads.
- Check uptime and minimum top-up: the cheapest provider is useless if it is down half the day.