GPT-4o vs OpenAI o4-mini
OpenAI o4-mini is cheaper for every workload modelled here.
List prices checked
Specifications and rates
| Property | GPT-4o | OpenAI o4-mini |
|---|---|---|
| Input per 1M | $2.50 | $1.10 |
| Output per 1M | $10.00 | $4.40 |
| Cached input per 1M | $1.25 | $0.275 |
| Blended (3:1) | $4.38 | $1.93 |
| Context window | 128K | 200K |
| Max output | 16K | 100K |
| Inputs accepted | text, image, audio | text, image |
Source: OpenAI pricing (May 2026) · OpenAI pricing (May 2026). Published list prices only — committed-use discounts, regional variation, and per-request charges are not included. Not yet independently re-checked against the vendor’s page.
Monthly cost by workload
Identical token volumes through both rate cards. Output-heavy profiles are where the ranking flips.
| Workload | GPT-4o | OpenAI o4-mini | Cheaper |
|---|---|---|---|
| In-app chat assistantA support or help assistant handling a few thousand conversations a month, with short prompts and short answers. | $100 | $44 | OpenAI o4-minisaves $56/mo (56%) |
| RAG over documentsRetrieval-augmented answering where each request stuffs several retrieved passages into the prompt, so input dominates. | $900 | $396 | OpenAI o4-minisaves $504/mo (56%) |
| Coding agentAn agentic loop that reads files and writes patches, generating heavy output and re-sending large context on every turn. | $2,000 | $880 | OpenAI o4-minisaves $1,120/mo (56%) |
What each one is for
GPT-4o
by OpenAI
The natively multimodal model that set the mid-market price for over a year. Now more expensive than newer models that outperform it, but still the default in a great deal of shipped code.
OpenAI o4-mini
by OpenAI
Cheap reasoning, strong on maths and code relative to its price. Same caveat as every reasoning model: budget for the thinking tokens, not just the visible answer.
Common questions
- Is GPT-4o or OpenAI o4-mini cheaper in 2026?
- OpenAI o4-mini, for every workload modelled here. On a blended 3:1 basis it costs $1.93 per million tokens against GPT-4o's $4.38.
- Which has the larger context window?
- OpenAI o4-mini, at 200K tokens against 128K. A larger window only helps if you can afford to fill it — the cost of one full-context request is in the table above.
- Which is cheaper for output-heavy work like agents?
- OpenAI o4-mini, at $4.40 per million output tokens against $10.00. Reasoning tokens bill as output, so for agentic loops this axis usually decides the invoice regardless of what the input rates look like.
- What is not included in these figures?
- Batch-processing discounts, fine-tuning, long-context surcharges above a provider's standard tier, and any enterprise agreement. These are published pay-as-you-go list prices, checked against each provider's own pricing page on the date shown.