DeepSeek R1 (0528) vs GPT-5.5
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
DeepSeek · May 2025
The open reasoning model that started it all — RL-trained chain-of-thought, MIT licensed, and a research landmark.
OpenAI · Apr 2026
OpenAI's flagship reasoning model with a 1M-token context window, built for hard coding, science and long-horizon agentic work.
The verdict
GPT-5.5 wins 3 of the 3 benchmarks these models share, against 0 for DeepSeek R1 (0528). On price the gap is dramatic: DeepSeek R1 (0528) works out roughly 12x cheaper per blended million tokens. GPT-5.5 also takes 1M of context versus 128K for DeepSeek R1 (0528). And DeepSeek R1 (0528) is open-weights (MIT), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
Benchmark head-to-head 0–3
Specs & pricing
| DeepSeek R1 (0528) | GPT-5.5 | |
|---|---|---|
| modhub Index | 67.8 | 77.2 |
| Input price / 1M | $0.55 | $5 |
| Output price / 1M | $2.19 | $30 |
| Context window | 128K | 1M |
| Max output | 64K | 128K |
| Open weights | yes (MIT) | no |
| Reasoning model | yes | yes |
| Multimodal input | text | text, image |
| Knowledge cutoff | Mar 2025 | Jan 2026 |
| Released | May 2025 | Apr 2026 |
| Example monthly cost* | $8.79 | $95.00 |
* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.
Frequently asked questions
- Which is better, DeepSeek R1 (0528) or GPT-5.5?
- GPT-5.5 wins 3 of the 3 benchmarks these models share, against 0 for DeepSeek R1 (0528). On price the gap is dramatic: DeepSeek R1 (0528) works out roughly 12x cheaper per blended million tokens. GPT-5.5 also takes 1M of context versus 128K for DeepSeek R1 (0528). And DeepSeek R1 (0528) is open-weights (MIT), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
- Which is cheaper, DeepSeek R1 (0528) or GPT-5.5?
- DeepSeek R1 (0528) costs $0.55/$2.19 per million input/output tokens, while GPT-5.5 costs $5/$30. For a typical workload of 10M input and 1.5M output tokens per month, that's $8.79 versus $95.00.
- Which model is better for coding, DeepSeek R1 (0528) or GPT-5.5?
- We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.