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DeepSeek V4 Pro vs GPT-5.6 Sol: pricing and benchmarks

DeepSeek V4 Pro is 67% cheaper on input tokens ($1.32 vs $4.00 per 1M). DeepSeek V4 Pro is 80% cheaper on output tokens ($3.96 vs $20.00 per 1M). On our document Q&A workload (50,000 questions a month), DeepSeek V4 Pro costs $646.80 a month versus $2,200 for GPT-5.6 Sol, 71% less. GPT-5.6 Sol scores 161.8 on the Epoch Capabilities Index vs 155.5 for DeepSeek V4 Pro.

Prices verified September 14, 2026.

Which should you choose?

Overall capability
GPT-5.6 Sol

GPT-5.6 Sol scores 161.8 on the Epoch Capabilities Index vs 155.5 for DeepSeek V4 Pro.

Advanced math
GPT-5.6 Sol

GPT-5.6 Sol scores 89.1% on FrontierMath (Tiers 1–3) vs 64.6% for DeepSeek V4 Pro.

Price
DeepSeek V4 Pro

DeepSeek V4 Pro costs $1.98 per 1M tokens (3:1 input-to-output mix) vs $8.00 for GPT-5.6 Sol, 75% less.

Best value
Too close to call

A trade-off: GPT-5.6 Sol is 6.3 ECI points more capable but costs 4.0x as much as DeepSeek V4 Pro.

Pricing and specs

DeepSeek V4 ProGPT-5.6 Sol
ProviderDeepSeekOpenAI
API model IDdeepseek-v4-progpt-5.6-sol
Input / 1M tokens$1.32$4.00
Cached input / 1M tokens$0.044$0.40
Output / 1M tokens$3.96$20.00
Long-context rates$8.00 in / $30.00 out on long-context requests
Context window1M tokens1.05M tokens
Max output384K tokens128K tokens
Batch discount50% off

Benchmarks

DeepSeek V4 ProGPT-5.6 Sol
Epoch Capabilities Index155.5161.8
GPQA Diamond· Science reasoning88.9%91.3%
FrontierMath (Tiers 1–3)· Advanced math64.6%89.1%
SimpleQA Verified· Factual accuracy52.9%69.7%
ARC-AGI-2· Abstract reasoning61.3%92.5%
DeepSWE· Coding72.7%
APEX-Agents· Agentic work40.0%

Source: Epoch AI, best recorded result per model (CC BY 4.0). A dash means no published score. See all benchmarks

Monthly cost for real workloads

WorkloadDeepSeek V4 ProGPT-5.6 SolDifference
Support chatbot
100,000 replies a month, ~1,500 input tokens (system prompt + history) and ~400 output tokens each.
$356.40$1,400DeepSeek V4 Pro 75% cheaper
Document Q&A (RAG)
50,000 questions a month with ~8,000 tokens of retrieved context and ~600 output tokens each.
$646.80$2,200DeepSeek V4 Pro 71% cheaper
Coding agent
10,000 agent steps a month, ~40,000 input tokens each (70% read from the prompt cache) and ~2,000 output tokens.
$249.92$992.00DeepSeek V4 Pro 75% cheaper

Estimates use standard list prices and ignore cache-write surcharges. Different tokenizers can count the same text differently, so test with your own prompts.

DeepSeek V4 Pro vs GPT-5.6 Sol cost calculator

Standard-tier list prices. Long-context rates apply automatically where the provider publishes a threshold. Excludes cache-write surcharges, taxes, batch and volume discounts.

DeepSeek V4 Pro pricing notes

DeepSeek’s larger V4 model with thinking and non-thinking modes and tool calls.

  • Prices shown are peak rates. Off-peak rates are half: peak hours are 01:00–04:00 and 06:00–10:00 UTC, Monday to Friday.
  • Vision input is not supported.
DeepSeek official pricing ↗

GPT-5.6 Sol pricing notes

OpenAI’s flagship GPT-5.6 model for complex professional work.

  • Promotional pricing, available at least through November 21, 2026.
  • Cache writes are billed at $5 per 1M tokens.
  • Regional (data residency) endpoints add a 10% uplift.
OpenAI official pricing ↗

Frequently asked questions

Is DeepSeek V4 Pro cheaper than GPT-5.6 Sol?
DeepSeek V4 Pro is 67% cheaper on input tokens ($1.32 vs $4.00 per 1M). DeepSeek V4 Pro is 80% cheaper on output tokens ($3.96 vs $20.00 per 1M). On our document Q&A workload (50,000 questions a month), DeepSeek V4 Pro costs $646.80 a month versus $2,200 for GPT-5.6 Sol, 71% less.
Which is more capable, DeepSeek V4 Pro or GPT-5.6 Sol?
GPT-5.6 Sol scores 161.8 on the Epoch Capabilities Index vs 155.5 for DeepSeek V4 Pro.
How much does DeepSeek V4 Pro cost per 1M tokens?
DeepSeek V4 Pro costs $1.32 per 1M input tokens and $3.96 per 1M output tokens, and $0.044 per 1M cached input tokens on DeepSeek’s standard tier.
How much does GPT-5.6 Sol cost per 1M tokens?
GPT-5.6 Sol costs $4.00 per 1M input tokens and $20.00 per 1M output tokens, and $0.40 per 1M cached input tokens on OpenAI’s standard tier.
Which has the larger context window, DeepSeek V4 Pro or GPT-5.6 Sol?
GPT-5.6 Sol has the larger context window: 1.05M tokens versus 1M for DeepSeek V4 Pro.

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