GPT-5 Pro (2025-10-06) vs GPT-6.1 Sol

Wins 0 of 4 benchmarks
$0.21 / task
Wins 0 of 4 benchmarks
GPT-5 Pro (2025-10-06)—
GPT-6.1 Sol49.9
GPT-5 Pro (2025-10-06)—
GPT-6.1 Sol48
GPT-5 Pro (2025-10-06)—
GPT-6.1 Sol62.6
GPT-5 Pro (2025-10-06)—
GPT-6.1 Sol83.9

Specs

SpecGPT-5 Pro (2025-10-06)GPT-6.1 Sol
Input, per 1M!$15$2
Output, per 1M!$120$10
Cost per task?—$0.21
Speed, tok/s—52
Context400K1.05M
WeightsNot verifiedClosed
ReleasedOct 2025Sep 2026
See images✓✓
Read PDFs?Partial
Hear audio——
Watch video——
Call tools✓✓
Force a tool call?Partial
Return strict JSON✓✓
Search the web?✓
Run code?✓
Use a computer?✓

What breaks when you switch

GPT-5 Pro (2025-10-06) → GPT-6.1 Sol
Remove unsupported parameters›

With reasoning enabled, remove temperature, top_p and top_logprobs, plus Chat Completions logprobs or Responses message.output_text.logprobs includes.

Responses API for tool calling · Chat Completions›

Use Responses for tools; Chat Completions supports this model without tool calling.

No none or minimal reasoning›

The none and minimal reasoning efforts are unsupported; choose low, medium, high, xhigh or max.

More than 272K input tokens›

Prompts above 272K input tokens charge 2× input and cache rates and 1.5× output rates for the entire request.

Cache writes billed at 1.25x›

Cache writes cost 1.25× the uncached input token rate.

Ultrafast prices 6x Standard›

Ultrafast mode costs 6× Standard token prices.

GPT-6.1 Sol → GPT-5 Pro (2025-10-06)
Context: 1.05M → 400K