GPT-4o vs Reasoning model (o-series): cost & margin
GPT-4o (OpenAI) and Reasoning model (o-series) (OpenAI) sit at different price points. At a typical 500k/150k token mix per customer, GPT-4o is cheaper ($2.75 vs $5.50 per customer), and GPT-4o has the lower output-token price — the part that usually drives an AI SaaS bill.
| GPT-4o | Reasoning model (o-series) | |
|---|---|---|
| Input $/Mtok | $2.5 | $5 |
| Output $/Mtok | $10 | $20 |
| Cost / customer (typical) | $2.75 | $5.50 |
| Margin at $49/mo | 94.4% | 88.8% |
Cost per customer as usage grows
Monthly LLM cost per customer at four usage levels — the gap widens the more your customers use.
| Usage / mo | GPT-4o | Reasoning model (o-series) |
|---|---|---|
| Light | $0.55 | $1.10 |
| Typical | $2.75 | $5.50 |
| Heavy | $11.00 | $22.00 |
| Power user | $45.00 | $90.00 |
Which should you pick?
GPT-4o
Best when cost is the priority: cheaper on both input and output, so it keeps more customers profitable at any plan price.
Reasoning model (o-series)
Worth it when its quality justifies the higher token cost — price your plans to cover the difference.
Verdict: at a typical token mix, GPT-4o is the cheaper choice per customer. Heavier or output-heavy workloads can change the picture — check yours below.
FAQ
- Which is cheaper, GPT-4o or Reasoning model (o-series)?
- At a typical 500k / 150k token mix, GPT-4o is cheaper — $2.75 vs $5.50 per customer per month, a $2.75 gap that widens as usage grows.
- Does Reasoning model (o-series) ever make more sense than GPT-4o?
- Yes — token price isn't everything. If Reasoning model (o-series) needs fewer retries or shorter outputs to finish the job, or its quality lifts conversion, it can be the better margin call despite the higher per-token price. Model it on your own usage.
Per-model details
Other comparisons