LLM Reference

DeepSeek V3.1 vs DeepSeek V4 Pro

DeepSeek V3.1 (2025) and DeepSeek V4 Pro (2026) are frontier reasoning models from DeepSeek. DeepSeek V3.1 ships a 64k-token context window, while DeepSeek V4 Pro ships a 1m-token context window. On MMLU PRO, DeepSeek V4 Pro leads by 4.2 pts. On pricing, DeepSeek V3.1 costs $0.27/1M input tokens versus $0.43/1M for the alternative. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

DeepSeek V3.1 is ~61% cheaper at $0.27/1M; pay for DeepSeek V4 Pro only for reasoning depth.

Decision scorecard

Local evidence first
SignalDeepSeek V3.1DeepSeek V4 Pro
Best formultimodal apps and provider-routed productionreasoning-heavy apps, tool-calling agents, and long-context analysis
Decision fitCoding, Agents, and VisionCoding, RAG, and Agents
Context window64k1m
Cheapest output$1/1M tokens$0.87/1M tokens
Provider routes8 tracked5 tracked
Shared benchmarks2 sharedMMLU PRO leader

Decision tradeoffs

Choose DeepSeek V3.1 when...
  • DeepSeek V3.1 has broader tracked provider coverage for fallback and route flexibility.
  • DeepSeek V3.1 uniquely exposes Vision, Multimodal, and Code execution in local model data.
  • Local decision data tags DeepSeek V3.1 for Coding, Agents, and Vision.
Choose DeepSeek V4 Pro when...
  • DeepSeek V4 Pro holds a shared-benchmark lead on MMLU PRO, ahead by 4.2 points.
  • DeepSeek V4 Pro has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • DeepSeek V4 Pro has the lower cheapest tracked output price at $0.87/1M tokens.
  • DeepSeek V4 Pro uniquely exposes Reasoning and JSON / Tool use in local model data.
  • Local decision data tags DeepSeek V4 Pro 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 V3.1

DeepSeek V3.1

$466

Cheapest tracked route/tier: Novita AI

DeepSeek V4 Pro

$566

Cheapest tracked route/tier: DeepSeek Platform

Estimated monthly gap: $99.50. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

DeepSeek V3.1 -> DeepSeek V4 Pro
  • Provider overlap exists on Fireworks AI, Vercel AI Gateway, and Novita AI; start route-level A/B tests there.
  • DeepSeek V4 Pro is $0.13/1M 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 and JSON / JSON / Tool use in local capability data.
DeepSeek V4 Pro -> DeepSeek V3.1
  • Provider overlap exists on Fireworks AI, Vercel AI Gateway, and Novita AI; start route-level A/B tests there.
  • DeepSeek V3.1 is $0.13/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Check replacement coverage for Reasoning and JSON / JSON / Tool use before moving production traffic.
  • DeepSeek V3.1 adds Vision, Multimodal, and Code execution in local capability data.

Specs

Specification
Released2025-08-212026-04-24
Context window64k1m
Parameters671B total, 37B active (MoE)1.6T
ArchitectureMixture of ExpertsMixture of Experts
LicenseMITOSI-approvedMITOSI-approved
OpennessOpen sourceOpen source
WeightsUnknownAvailable
CodeUnknownUnknown
Commercial useCommercial use: permittedCommercial use: permitted
Knowledge cutoff--

Pricing and availability

Pricing attributeDeepSeek V3.1DeepSeek V4 Pro
Input price$0.27/1M tokens$0.43/1M tokens
Output price$1/1M tokens$0.87/1M tokens
Providers

Capabilities

CapabilityDeepSeek V3.1DeepSeek V4 Pro
VisionYesNo
MultimodalYesNo
ReasoningNoYes
JSON / Tool useNoYes
Structured outputsYesYes
Code executionYesNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

BenchmarkDeepSeek V3.1DeepSeek V4 Pro
MMLU PRO83.387.5
SWE-bench Verified66.080.6

Continue comparing

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