Comparison
GPT-4o vs GPT-5.5
Per input token, GPT-4o runs 50% cheaper than GPT-5.5. Output pricing favors GPT-4o, 67% less per token than GPT-5.5. GPT-5.5 accepts more context per request than GPT-4o.
Worked cost examples
Estimated monthly cost on three common usage shapes
| Workload | GPT-4o | GPT-5.5 |
|---|---|---|
Chatbot 800 input / 200 output tokens per request, 100,000 requests/month | $400.00cheaper | $1,000 |
RAG pipeline 6,000 input / 700 output tokens per request, 30,000 requests/month | $660.00cheaper | $1,530 |
Batch summarization 20,000 input / 1,500 output tokens per request, 5,000 requests/month | $325.00cheaper | $725.00 |
GPT-4o vs GPT-5.5 FAQ
- Is GPT-4o cheaper than GPT-5.5?
- GPT-4o costs $2.50 per 1M input tokens versus $5.00 for GPT-5.5 — GPT-4o is 50% cheaper per input token.
- Which is cheaper for output tokens, GPT-4o or GPT-5.5?
- GPT-4o charges $10.00 per 1M output tokens; GPT-5.5 charges $30.00 per 1M output tokens.
- Which has the larger context window, GPT-4o or GPT-5.5?
- GPT-5.5 does, with a 1,050,000-token context window.
- Do GPT-4o and GPT-5.5 offer cache pricing?
- GPT-4o discounts cached input to $1.25 per 1M tokens. GPT-5.5 discounts cached input to $0.50 per 1M tokens.
Looking for another matchup? See all comparisons.