LLM Reference

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 MMLU PRO, Gemini 3.1 Pro Preview leads by 3.5 pts. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

DeepSeek V4 Pro is safer overall; choose Gemini 3.1 Pro Preview when coding workflow support matters.

Decision scorecard

Local evidence first
SignalDeepSeek V4 ProGemini 3.1 Pro Preview
Best forreasoning-heavy apps, tool-calling agents, and long-context analysismultimodal apps, tool-calling agents, and long-context analysis
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window1m1m
Cheapest output$0.87/1M tokens$12/1M tokens
Provider routes5 tracked5 tracked
Shared benchmarks11 sharedMMLU PRO leader

Decision tradeoffs

Choose DeepSeek V4 Pro when...
  • DeepSeek V4 Pro holds a shared-benchmark lead on SWE-bench Pro, ahead by 1.2 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 holds a shared-benchmark lead on MMLU PRO, ahead by 3.5 points.
  • 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 route or tier on this page.

Lower estimate DeepSeek V4 Pro

DeepSeek V4 Pro

$566

Cheapest tracked route/tier: DeepSeek Platform

Gemini 3.1 Pro Preview

$4,600

Cheapest tracked route/tier: Google AI Studio

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

Switch friction

DeepSeek V4 Pro -> Gemini 3.1 Pro Preview
  • Provider overlap exists on OpenRouter and Vercel AI Gateway; 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 and Vercel AI Gateway; 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
LicenseMITOSI-approvedProprietary
OpennessOpen sourceProprietary
WeightsAvailableNot released
CodeUnknownUnknown
Commercial useCommercial use: permittedCommercial use: conditional
Knowledge cutoff-2025-01

Pricing and availability

Pricing attributeDeepSeek V4 ProGemini 3.1 Pro Preview
Input price$0.43/1M tokens
0-200,001t
$2/1M tokens
200,001t+
$4/1M tokens
Output price$0.87/1M tokens
0-200,001t
$12/1M tokens
200,001t+
$18/1M tokens
Providers

Capabilities

CapabilityDeepSeek V4 ProGemini 3.1 Pro Preview
VisionNoYes
MultimodalNoYes
ReasoningYesNo
JSON / Tool useYesYes
Structured outputsYesYes
Code executionNoYes
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

BenchmarkDeepSeek V4 ProGemini 3.1 Pro Preview
MMLU PRO87.591.0
SWE-bench Verified80.680.6
SWE-bench Pro55.454.2
Google-Proof Q&A90.194.3
LiveCodeBench93.591.7
Humanity's Last Exam37.751.4
HumanEval76.894.0
Chatbot Arena1456.01493.0
Massive Multitask Language Understanding90.198.0
BrowseComp83.485.9
MCP-Atlas69.469.2

Continue comparing

Last reviewed: 2026-06-29. Data sourced from public model cards and provider documentation.