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DeepSeek R1 vs o3

DeepSeek R1 (2025) and o3 (2025) are frontier-tier reasoning models from DeepSeek and OpenAI. DeepSeek R1 ships a 128K-token context window, while o3 ships a 200K-token context window. On SWE-bench Verified, o3 leads by 22.5 pts. On pricing, DeepSeek R1 costs $0.1/1M input tokens versus $2/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.

DeepSeek R1 is ~1900% cheaper at $0.1/1M; pay for o3 only for coding workflow support.

Specs

Specification
Released2025-01-202025-03-31
Context window128K200K
Parameters671B, 37B Active
Architecturedecoder onlydecoder only
LicenseOpen SourceProprietary
Knowledge cutoff--

Pricing and availability

Pricing attributeDeepSeek R1o3
Input price$0.1/1M tokens$2/1M tokens
Output price$0.3/1M tokens$8/1M tokens
Providers

Capabilities

CapabilityDeepSeek R1o3
VisionNoNo
MultimodalNoNo
ReasoningYesYes
Function callingNoNo
Tool useNoNo
Structured outputsYesYes
Code executionYesYes

Benchmarks

BenchmarkDeepSeek R1o3
SWE-bench Verified49.271.7
Google-Proof Q&A71.587.7
HumanEval89.996.7
Chatbot Arena1372.01412.0
Aider Polyglot56.981.3

Deep dive

On shared benchmark coverage, SWE-bench Verified has DeepSeek R1 at 49.2 and o3 at 71.7, with o3 ahead by 22.5 points; Google-Proof Q&A has DeepSeek R1 at 71.5 and o3 at 87.7, with o3 ahead by 16.2 points; HumanEval has DeepSeek R1 at 89.9 and o3 at 96.7, with o3 ahead by 6.8 points. The largest visible gap is 22.5 points on SWE-bench Verified, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.

The capability footprint is close: both models cover reasoning mode, structured outputs, and code execution. That makes context budget, benchmark fit, and provider maturity more important than a simple checklist. If your application depends on one integration detail, verify it against the provider route you plan to use, not just the base model listing.

For cost, DeepSeek R1 lists $0.1/1M input and $0.3/1M output tokens, while o3 lists $2/1M input and $8/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts DeepSeek R1 lower by about $3.64 per million blended tokens. Availability is 13 providers versus 2, so concentration risk also matters.

Choose DeepSeek R1 when coding workflow support, lower input-token cost, and broader provider choice are central to the workload. Choose o3 when coding workflow support and larger context windows are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.

FAQ

Which has a larger context window, DeepSeek R1 or o3?

o3 supports 200K tokens, while DeepSeek R1 supports 128K tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is cheaper, DeepSeek R1 or o3?

DeepSeek R1 is cheaper on tracked token pricing. DeepSeek R1 costs $0.1/1M input and $0.3/1M output tokens. o3 costs $2/1M input and $8/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is DeepSeek R1 or o3 open source?

DeepSeek R1 is listed under Open Source. o3 is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.

Which is better for reasoning mode, DeepSeek R1 or o3?

Both DeepSeek R1 and o3 expose reasoning mode. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for structured outputs, DeepSeek R1 or o3?

Both DeepSeek R1 and o3 expose structured outputs. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Where can I run DeepSeek R1 and o3?

DeepSeek R1 is available on DeepSeek Platform, OpenRouter, Together AI, Fireworks AI, and NVIDIA NIM. o3 is available on OpenAI API and OpenRouter. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-05-11. Data sourced from public model cards and provider documentation.