Which is cheaper, DeepSeek V4 Pro and GPT-6 Sol?

DeepSeek V4 Pro has the lowest input price. Per 1M input tokens: DeepSeek V4 Pro from $1.74 and GPT-6 Sol from $2.00.

Which has the larger context window, DeepSeek V4 Pro and GPT-6 Sol?

DeepSeek V4 Pro has the largest context window: DeepSeek V4 Pro 1,048,576 tokens and GPT-6 Sol 400,000 tokens.

Can I switch between DeepSeek V4 Pro and GPT-6 Sol without changing my code?

Yes. All of them are served through FastRouter's OpenAI-compatible API, so switching is a change of the model parameter (deepseek/deepseek-v4-pro, openai/gpt-6-sol).

DeepSeek V4 Pro vs GPT-6 Sol

Side-by-side pricing per provider, context window, benchmark scores and speed, all on one OpenAI-compatible API.

Estimate monthly cost for these models

DeepSeek V4 Pro DeepSeekdeepseek/deepseek-v4-pro

GPT-6 Sol OpenAIopenai/gpt-6-sol

Creator

DeepSeek

OpenAI

Released

Apr 24, 2026

Sep 22, 2026

Context window

1.05M

400K

Max output

384K

128K

Input / 1MLowest provider price

$1.74$1.74–$2.40 across 3

$2.00

Output / 1MLowest provider price

$3.48$3.48–$4.80 across 3

$10.00

Providers

IntelligenceArtificial Analysis index

23.1

44.1

LatencyMedian time to first token

4.9s

—

ThroughputMedian tokens per second

<1 t/s

—

Accepts

Text

Files, Image, Text

Produces

Text

Tool calling

Yes

Structured output

Yes

Reasoning

Yes

DeepSeek V4 Pro vs GPT-6 Sol: summary

DeepSeek V4 Pro and GPT-6 Sol are both available through FastRouter's OpenAI-compatible API, so switching between them is a change of model id, not a new integration.

DeepSeek V4 Pro, from DeepSeek, has a 1,048,576-token context window, costs from $1.74/1M input and $3.48/1M output tokens across 3 providers and scores 23.1 on the Artificial Analysis Intelligence Index.

GPT-6 Sol, from OpenAI, has a 400,000-token context window, costs $2.00/1M input and $10.00/1M output tokens and scores 44.1 on the Artificial Analysis Intelligence Index.

DeepSeek V4 Pro is the cheapest on input, 1.1× cheaper than the next model, DeepSeek V4 Pro has the largest context window and GPT-6 Sol scores highest for intelligence.

Switch with one line

client = OpenAI(base_url="https://api.fastrouter.ai/api/v1", api_key="<FASTROUTER_API_KEY>") client.chat.completions.create(model="deepseek/deepseek-v4-pro", messages=[...]) # or client.chat.completions.create(model="openai/gpt-6-sol", messages=[...])

Full API docs

Frequently asked questions

More comparisons

Benchmark scores sourced from ArtificialAnalysis