DeepSeek-R1 vs GPT-5.5
A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.
Updated
DeepSeek-R1 specs · GPT-5.5 specs- PriceDeepSeek-R1
DeepSeek-R1 publishes pricing ($2.19 / 1M output tokens) while GPT-5.5 does not.
- Context windowGPT-5.5
GPT-5.5 accepts 400K tokens vs 128K, 3.1× the room for long documents and codebases.
- BenchmarksTie
No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores.
- ModalitiesGPT-5.5
GPT-5.5 supports 3 modalities (text, vision, audio) vs 1 for DeepSeek-R1.
- OpennessDeepSeek-R1
DeepSeek-R1 ships open weights (MIT); GPT-5.5 is API-only.
It's a genuine coin-flip between DeepSeek-R1 and GPT-5.5: 2 category wins each, with the rest tied. DeepSeek-R1 publishes pricing ($2.19 / 1M output tokens) while GPT-5.5 does not. GPT-5.5 accepts 400K tokens vs 128K, 3.1× the room for long documents and codebases.
No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores. They differ in modality coverage, DeepSeek-R1 handles text while GPT-5.5 handles text, vision, audio, which can be the deciding factor before you even look at benchmarks. DeepSeek-R1 ships open weights (MIT); GPT-5.5 is API-only.
GPT-5.5 is the newer of the two, released 14 months after DeepSeek-R1, which usually means a more recent knowledge cutoff and updated safety post-training. DeepSeek-R1 is usually picked for reasoning and math workloads, while GPT-5.5 sees more deployments in agents and tool use. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.
Side-by-side specs
| Spec | DeepSeek-R1 | GPT-5.5 |
|---|---|---|
| Provider | DeepSeek | OpenAI |
| Released | Jan 2025 | Mar 2026 |
| Modalities | text | text, vision, audio |
| Context window | 128K tokens | 400K tokens |
| Max output | , | , |
| Input · 1M | $0.55 / 1M tokens | Pricing not published |
| Output · 1M | $2.19 / 1M tokens | Pricing not published |
| Knowledge cutoff | 2024-07 | , |
| Open weights | Yes (MIT) | No |
| API available | Yes | Yes |
Pricing at scale
What you'd actually pay at typical workloads. Numbers come from each model's published per-million-token rates.
- Light usage, 100k in / 50k out per day$4.94 vs ,
- Heavy usage, 1M in / 500k out per day$49.35 vs ,
- RAG workload, 5M in / 200k out per day$95.64 vs ,
Light usage, 100k in / 50k out per day: pricing not directly comparable (one or both models are missing public per-token rates). Heavy usage, 1M in / 500k out per day: pricing not directly comparable (one or both models are missing public per-token rates). RAG workload, 5M in / 200k out per day: pricing not directly comparable (one or both models are missing public per-token rates).
Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.
- DeepSeek-R1$0.165
- GPT-5.5Pricing unavailable
Benchmarks compared
Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.
- GPQA71.5
DeepSeek-R1 fits when…
- Open-weight reasoning model on par with o1
- MIT license
- Cheap reasoning per token
- Self-hosting and on-prem requirements, open weights (MIT).
GPT-5.5 fits when…
- Industry-leading tool-use and function-calling reliability
- Strong end-to-end agent performance across SWE-bench and GAIA
- Wide ecosystem support, ChatGPT, Realtime API, Responses API
- Long-context tasks, handles 400K tokens vs 128K for DeepSeek-R1.
- Multimodal needs covering vision, audio.
Consider DeepSeek-V3
DeepSeek's flagship 671B-parameter MoE, frontier-level quality at a tiny fraction of frontier prices.
Frequently asked
Is DeepSeek-R1 or GPT-5.5 cheaper?
Per-token pricing isn't published for at least one of these models, check each model's spec page for current rates.Which has the larger context window?
GPT-5.5 accepts 400K tokens vs 128K for DeepSeek-R1.Is DeepSeek-R1 or GPT-5.5 better for coding?
Both DeepSeek-R1 and GPT-5.5 are competitive on coding benchmarks. See each model's individual spec page for HumanEval and SWE-bench scores where published. For an opinionated pick, consult our Best LLM for Coding ranking.Are either of these models open source?
DeepSeek-R1 ships open weights (MIT). GPT-5.5 is API-only.When were DeepSeek-R1 and GPT-5.5 released?
DeepSeek-R1 was released by DeepSeek on 2025-01-20. GPT-5.5 was released by OpenAI on 2026-03-01.
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