OPENAI VS DEEPSEEK

GPT-5.6 Sol vs DeepSeek V4 Flash

DeepSeek V4 Flash is about 64x cheaper than GPT-5.6 Sol on a blended 3:1 input:output rate — the same 10K-in/2K-out request costs $0.002 vs $0.11. GPT-5.6 Sol has the larger context window (1,047,576 vs 1,000,000 tokens).

Pricing verified

API pricing per 1M tokens

ModelInput / 1M tokensOutput / 1M tokensBlended (3:1 mix)
GPT-5.6 Sol$5.00$30.00$11.25
DeepSeek V4 Flash$0.14$0.28$0.175

Rates from official OpenAI pricing and official DeepSeek pricing, checked 2026-08-11.

What a real workload costs

Example: one request with 10,000 input tokens and 2,000 output tokens, then that request at 100,000 runs per month.

ModelPer request (10K in / 2K out)Per month (100K requests)Monthly delta
GPT-5.6 Sol$0.11$11,000+$10,804
DeepSeek V4 Flash$0.002$196—

Model your own prompt sizes and volumes in the token cost analyzer, or check caching savings with the prompt caching calculator.

Specs side by side

SpecGPT-5.6 SolDeepSeek V4 Flash
ProviderOpenAIDeepSeek
Context window1,047,576 tokens1,000,000 tokens
Model classGeneral textGeneral text
Tokenizero200k_base (exact, public)Proprietary (counts estimated)

Count tokens for each model on its own page: GPT-5.6 Sol token counter and DeepSeek V4 Flash token counter. All OpenAI models are on the OpenAI Token Counter. All DeepSeek models are on the DeepSeek Token Counter.

FAQ

GPT-5.6 Sol vs DeepSeek V4 Flash FAQ

Which is cheaper, GPT-5.6 Sol or DeepSeek V4 Flash?

DeepSeek V4 Flash is cheaper. At rates checked 2026-08-11, GPT-5.6 Sol costs $5.00 input / $30.00 output per 1M tokens, while DeepSeek V4 Flash costs $0.14 input / $0.28 output — about a 64x difference on a typical 3:1 input-heavy workload.

How much does a real request cost on GPT-5.6 Sol vs DeepSeek V4 Flash?

A request with 10,000 input tokens and 2,000 output tokens costs about $0.11 on GPT-5.6 Sol and $0.002 on DeepSeek V4 Flash. At 100,000 such requests per month that is $11,000 vs $196 — a difference of $10,804 per month.

Which has the bigger context window, GPT-5.6 Sol or DeepSeek V4 Flash?

GPT-5.6 Sol. It supports 1,047,576 tokens of context versus 1,000,000 tokens — roughly 786,000 English words in one request.

Do GPT-5.6 Sol and DeepSeek V4 Flash count tokens the same way?

Not exactly. GPT-5.6 Sol uses the published o200k_base tokenizer and DeepSeek V4 Flash uses a proprietary tokenizer (counts are estimates). The same prompt will tokenize differently, which shifts effective cost per word.