OpenAI o3 vs DeepSeek R1: Reasoning Model Cost Comparison 2026
How much cheaper is DeepSeek R1 than o3? Benchmark scores, monthly cost at scale, and which reasoning model to choose for your workload.
OpenAI o3 and DeepSeek R1 are both reasoning models — they use extended chain-of-thought to solve complex math, science, and coding problems. But the price difference is enormous. This guide compares cost, performance, and the realistic scenarios where each one makes sense.
Pricing Comparison
Cost at Scale: Monthly Comparison
At 1,000 reasoning requests/day (3K input + 2K output tokens, before reasoning overhead):
Performance: Where Each Model Wins
Benchmarks (as of 2026)
o3 leads on most hard reasoning benchmarks, particularly competitive coding and frontier math. DeepSeek R1 is competitive on math and significantly stronger than its price would suggest — but there's a measurable quality gap at the top end.
When to Use Each
o4-mini: The Sweet Spot?
OpenAI's o4-mini sits between o3 and DeepSeek R1 on both price and performance. For teams that need OpenAI reliability with better economics than o3, o4-mini is often the right call. It scores close to o3 on most benchmarks at roughly -175% lower input cost.
Compare directly: DeepSeek R1 vs o3 → | DeepSeek pricing →