Skip to main content
AI Choice EngineAI Choice Engine

Model comparison

DeepSeek V4 Pro vs GPT-5.6 Sol

DeepSeek against OpenAI, compared on context, price, and verified benchmark results.

Catalog record checked September 3, 2026Individual provider fields may changeEvidence confidence: High — see receipts below

DeepSeek

DeepSeek V4 Pro

Frontier · Open weights

vs

OpenAI

GPT-5.6 Sol

Frontier

AI model capability comparison
SpecificationDeepSeek V4 ProGPT-5.6 Sol
ProviderDeepSeekOpenAI
TierFrontierFrontier
Context window1MWinner: 1.05M
Max outputWinner: 384K128K
Input / 1M tokensWinner: $1.32$4
Output / 1M tokensWinner: $3.96$20
WeightsOpenClosed
Parameters1.6T total / 49B active (MoE)flagship reasoning + coding model
Reasoning levelslow, high, maxnone, low, medium, high, xhigh, max
Modalitiestexttext, image
LicenseMITNot disclosedUnverified
API model iddeepseek-v4-progpt-5.6-sol
ReleasedApril 24, 2026July 9, 2026
Artificial Analysis Intelligence Index (2026-08-14)53Not verifiedUnverified
Artificial Analysis Intelligence Index [max] (2026-08-14)Not verifiedUnverified61
SWE-bench Verified (2026-04-24)80.6Not verifiedUnverified
GPQA Diamond (2026-04-24)90.1Winner: 94.6
Humanity's Last Exam (2026-04-24)48.2Not verifiedUnverified
MMLU-Pro (2026-04-24)87.5Not verifiedUnverified
Terminal-Bench 2.1 (2026-07-09)Not verifiedUnverified88.8

Prices are USD per million tokens at standard rates, excluding batch and caching discounts. Bold indicates the better figure where one is objectively better. Values we could not confirm from the provider are shown as “Not verified” rather than estimated.

Benchmark receipts

  • 2026-08-14: Artificial AnalysisComposite index blending reasoning, knowledge, and coding evals into one 0–100 score. Comparability: directly comparable — AA occasionally rebaselines the index scale between snapshots — a score captured on one date is only comparable to same-snapshot scores (check measuredAt).
  • 2026-07-09: OpenAI — GPT-5.6 evals table (vendor)Agentic terminal work: multi-step tasks executed in a sandboxed shell environment. Comparability: comparable with caveat — Scores across Terminal-Bench major versions (v1 vs v2) are NOT comparable; harness configuration (container, time limits) also shifts results.
  • 2026-04-24: DeepSeek V4 Pro HF model card (vendor, Think Max, exact match)Real GitHub issue resolution: does the model's patch pass the hidden tests. Comparability: comparable with caveat — Post-audit vendor claims and pre-audit scores sit on different task trust levels; scaffolding (agent harness, compute budget) also dominates results. Never aggregate across scaffolds.

Pricing tiers: DeepSeek V4 Pro: Official peak rates $1.32/$3.96 per MTok; off-peak $0.66/$1.98 (cache-miss). Open weights (MIT). 1.6T/49B active MoE. · GPT-5.6 Sol: Launch list was $5/$30; cut to $4/$20 on 2026-08-21, promo held at least through 2026-11-21. Cached input $0.40/MTok; batch $2/$10. Knowledge cutoff Feb 16 2026.

FrontierOpen weightsRecord checked September 3, 2026

DeepSeek V4 Pro

DeepSeek V4 Pro is the open-weight (MIT) flagship with a 1M-token context at a fraction of frontier API cost.

Best for

  • Cost-sensitive hosted agents
  • Open-weight deployments
  • High-volume coding

Watch out

Self-hosting needs datacentre VRAM; hosted rates vary by provider. Price single-source — verify.

FrontierRecord checked September 3, 2026

GPT-5.6 Sol

OpenAI's GPT-5.6 flagship for complex reasoning and coding with a 1.05M-token context — top-tier but no longer the agentic-coding leader on the tracked boards.

Best for

  • Complex reasoning
  • Agentic coding
  • Hard knowledge work

Watch out

At $4/$20 per MTok it is the priciest GPT-5.6 tier; 'max' effort and 'ultra' multi-agent mode multiply token use.

When the cheaper one wins

DeepSeek V4 Pro is cheaper on output at $3.96 per million tokens against $20 for GPT-5.6 Sol — about 5.1×. Use the cheaper tier for classification, extraction, summarisation, and any task where the expensive model’s extra score does not change the accepted output. The expensive one only pays if your hardest task actually fails on the cheap tier. These are standard-tier API rates, excluding batch and cache discounts.

Run the model picker

Evidence confidence: High

How strong and complete the evidence behind this comparison is — not a prediction of which model is better.

  • Pricing verified on both sidesInput and output rates are verified for both models.
  • 5/5 core specs verified on both sidesAll core specifications verified for both models.
  • 2 shared named benchmarks with differing scoresMeasured on: Artificial Analysis Intelligence Index, GPQA Diamond.
  • Verified within the last 90 daysNewest catalog check was 8 days ago.
  • Both models carry source citationsEach side has at least two catalog sources on record.

Source receipts

Each catalog figure was checked against the provider or an independent second source on the date shown.

Common questions

DeepSeek V4 Pro vs GPT-5.6 Sol

Answered from the verified figures on this page rather than general guidance.

Is DeepSeek V4 Pro or GPT-5.6 Sol cheaper for input?

DeepSeek V4 Pro is cheaper at $1.32 per million input tokens, against $4 for GPT-5.6 Sol — roughly 3.0× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; DeepSeek V4 Pro has tiered pricing: Official peak rates $1.32/$3.96 per MTok; off-peak $0.66/$1.98 (cache-miss). Open weights (MIT). 1.6T/49B active MoE. GPT-5.6 Sol has tiered pricing: Launch list was $5/$30; cut to $4/$20 on 2026-08-21, promo held at least through 2026-11-21. Cached input $0.40/MTok; batch $2/$10. Knowledge cutoff Feb 16 2026.

Is DeepSeek V4 Pro or GPT-5.6 Sol cheaper for output?

DeepSeek V4 Pro is cheaper at $3.96 per million output tokens, against $20 for GPT-5.6 Sol — roughly 5.1× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; DeepSeek V4 Pro has tiered pricing: Official peak rates $1.32/$3.96 per MTok; off-peak $0.66/$1.98 (cache-miss). Open weights (MIT). 1.6T/49B active MoE. GPT-5.6 Sol has tiered pricing: Launch list was $5/$30; cut to $4/$20 on 2026-08-21, promo held at least through 2026-11-21. Cached input $0.40/MTok; batch $2/$10. Knowledge cutoff Feb 16 2026.

Which has the larger context window, DeepSeek V4 Pro or GPT-5.6 Sol?

GPT-5.6 Sol accepts 1.05M tokens against 1M for DeepSeek V4 Pro. This only matters if you routinely send very long documents or large codebases.

Do DeepSeek V4 Pro and GPT-5.6 Sol support the same reasoning levels?

DeepSeek V4 Pro exposes low, high, max, while GPT-5.6 Sol exposes none, low, medium, high, xhigh, max.

Should I use DeepSeek V4 Pro or GPT-5.6 Sol?

Both sit in the frontier tier, so the choice usually comes down to price and context rather than capability. DeepSeek V4 Pro suits cost-sensitive hosted agents; GPT-5.6 Sol suits complex reasoning.

Can I self-host DeepSeek V4 Pro or GPT-5.6 Sol?

DeepSeek V4 Pro publishes open weights, but self-hosting and third-party provider access depend on the licence, hardware, serving support, and availability. GPT-5.6 Sol is a closed model whose supported access paths are controlled by its provider.

Next step

Choosing between them

The verified figures that separate this pair, computed from the catalog rather than restated boilerplate.

  • Input price: DeepSeek V4 Pro costs $1.32 per 1M tokens versus $4 for GPT-5.6 Sol — a 3x difference at the headline tier.
  • Context: GPT-5.6 Sol takes 1.05M against 1M for DeepSeek V4 Pro — only decisive if your prompts approach the smaller window.
  • Measured capability: GPT-5.6 Sol leads Artificial Analysis Intelligence Index 61 to 53 (measured 2026-08-14).
  • Deployment: DeepSeek V4 Pro publishes weights you can self-host; the other is API-only.

Choosing a harness rather than a model — Cursor, Copilot, Claude Code, Windsurf, or Lovable? Compare agentic harnesses · Latest releases.