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DeepSeek V4 Pro vs Gemini 3.1 Pro Preview

DeepSeek V4 Pro (2026) and Gemini 3.1 Pro Preview (2026) are frontier reasoning models from DeepSeek and Google DeepMind. DeepSeek V4 Pro ships a 1M-token context window, while Gemini 3.1 Pro Preview ships a 1M-token context window. On SWE-bench Verified, DeepSeek V4 Pro leads by a hair. On pricing, DeepSeek V4 Pro costs $0.43/1M input tokens versus $2/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.

DeepSeek V4 Pro is ~360% cheaper at $0.43/1M; pay for Gemini 3.1 Pro Preview only for coding workflow support.

Decision scorecard

Local evidence first
SignalDeepSeek V4 ProGemini 3.1 Pro Preview
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window1M1M
Cheapest output$0.87/1M tokens$12/1M tokens
Provider routes3 tracked4 tracked
Shared benchmarksSWE-bench Verified leader4 rows

Decision tradeoffs

Choose DeepSeek V4 Pro when...
  • DeepSeek V4 Pro leads the largest shared benchmark signal on SWE-bench Verified by 0 points.
  • DeepSeek V4 Pro has the lower cheapest tracked output price at $0.87/1M tokens.
  • DeepSeek V4 Pro uniquely exposes Reasoning in local model data.
  • Local decision data tags DeepSeek V4 Pro for Coding, RAG, and Agents.
Choose Gemini 3.1 Pro Preview when...
  • Gemini 3.1 Pro Preview leads the largest shared benchmark signal on Google-Proof Q&A by 4.2 points.
  • Gemini 3.1 Pro Preview has broader tracked provider coverage for fallback and procurement flexibility.
  • Gemini 3.1 Pro Preview uniquely exposes Vision, Multimodal, and Code execution in local model data.
  • Local decision data tags Gemini 3.1 Pro Preview for Coding, RAG, and Agents.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output prices on this page.

Lower estimate DeepSeek V4 Pro

DeepSeek V4 Pro

$566

Cheapest tracked route: DeepSeek Platform

Gemini 3.1 Pro Preview

$4,600

Cheapest tracked route: Google AI Studio

Estimated monthly gap: $4,035. Batch, cache, and negotiated pricing are excluded from this local estimate.

Switch friction

DeepSeek V4 Pro -> Gemini 3.1 Pro Preview
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • Gemini 3.1 Pro Preview is $11.13/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Check replacement coverage for Reasoning before moving production traffic.
  • Gemini 3.1 Pro Preview adds Vision, Multimodal, and Code execution in local capability data.
Gemini 3.1 Pro Preview -> DeepSeek V4 Pro
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • DeepSeek V4 Pro is $11.13/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Vision, Multimodal, and Code execution before moving production traffic.
  • DeepSeek V4 Pro adds Reasoning in local capability data.

Specs

Specification
Released2026-04-242026-02-19
Context window1M1M
Parameters1.6T
Architecturemixture of expertsdecoder only
LicenseMITProprietary
Knowledge cutoff-2025-01

Pricing and availability

Pricing attributeDeepSeek V4 ProGemini 3.1 Pro Preview
Input price$0.43/1M tokens$2/1M tokens
Output price$0.87/1M tokens$12/1M tokens
Providers

Capabilities

CapabilityDeepSeek V4 ProGemini 3.1 Pro Preview
VisionNoYes
MultimodalNoYes
ReasoningYesNo
Function callingYesYes
Tool useYesYes
Structured outputsYesYes
Code executionNoYes

Benchmarks

BenchmarkDeepSeek V4 ProGemini 3.1 Pro Preview
SWE-bench Verified80.680.6
Google-Proof Q&A90.194.3
Chatbot Arena1460.01493.0
SWE-bench Pro55.454.2

Deep dive

On shared benchmark coverage, SWE-bench Verified has DeepSeek V4 Pro at 80.6 and Gemini 3.1 Pro Preview at 80.6, with DeepSeek V4 Pro ahead by 0 points; Google-Proof Q&A has DeepSeek V4 Pro at 90.1 and Gemini 3.1 Pro Preview at 94.3, with Gemini 3.1 Pro Preview ahead by 4.2 points; Chatbot Arena has DeepSeek V4 Pro at 1460 and Gemini 3.1 Pro Preview at 1493, with Gemini 3.1 Pro Preview ahead by 33 points. The largest visible gap is 33 points on Chatbot Arena, 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 differs most on vision: Gemini 3.1 Pro Preview, multimodal input: Gemini 3.1 Pro Preview, reasoning mode: DeepSeek V4 Pro, and code execution: Gemini 3.1 Pro Preview. Both models share function calling, tool use, and structured outputs, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.

For cost, DeepSeek V4 Pro lists $0.43/1M input and $0.87/1M output tokens, while Gemini 3.1 Pro Preview lists $2/1M input and $12/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts DeepSeek V4 Pro lower by about $4.43 per million blended tokens. Availability is 3 providers versus 4, so concentration risk also matters.

Choose DeepSeek V4 Pro when reasoning depth and lower input-token cost are central to the workload. Choose Gemini 3.1 Pro Preview when coding workflow support and broader provider choice 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 V4 Pro or Gemini 3.1 Pro Preview?

DeepSeek V4 Pro supports 1M tokens, while Gemini 3.1 Pro Preview supports 1M tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Which is cheaper, DeepSeek V4 Pro or Gemini 3.1 Pro Preview?

DeepSeek V4 Pro is cheaper on tracked token pricing. DeepSeek V4 Pro costs $0.43/1M input and $0.87/1M output tokens. Gemini 3.1 Pro Preview costs $2/1M input and $12/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is DeepSeek V4 Pro or Gemini 3.1 Pro Preview open source?

DeepSeek V4 Pro is listed under MIT. Gemini 3.1 Pro Preview 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 vision, DeepSeek V4 Pro or Gemini 3.1 Pro Preview?

Gemini 3.1 Pro Preview has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Which is better for multimodal input, DeepSeek V4 Pro or Gemini 3.1 Pro Preview?

Gemini 3.1 Pro Preview has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run DeepSeek V4 Pro and Gemini 3.1 Pro Preview?

DeepSeek V4 Pro is available on DeepSeek Platform, Fireworks AI, and OpenRouter. Gemini 3.1 Pro Preview is available on Google AI Studio, GCP Vertex AI, OpenRouter, and Replicate API. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-05-14. Data sourced from public model cards and provider documentation.