Compare AI models

Specifications
ParametersA rough measure of how big the model is. More parameters usually means more capable and more expensive to run, though it is a poor guide on its own — a smaller, newer model often beats a larger, older one.
—117B
Context windowHow much text the model can hold in mind at once — your question, any documents you attach, the conversation so far, and its own reply. Go past it and the earliest part falls out of view.
128k128k
API pricingUSD per 1M tokens · lower wins
Input priceWhat you pay for everything you send the model — your question, plus any documents or earlier conversation you include with it.
$0.15—
Output priceWhat you pay for the text the model writes back. It is normally the dearer half: producing an answer costs more than reading one.
$0.60—
Cached input priceA reduced rate for text you send over and over. If every request starts with the same instructions or the same document, the provider keeps a copy ready and charges less to read it again.
$0.075—
Cheapest inputLowest input rate across every provider on OpenRouter, the lab included. The cheapest endpoint may run a quantised build or a shorter context — see "Available from" on the model page.
$0.15Azure$0.03AkashML
Cheapest outputLowest output rate across every provider on OpenRouter, the lab included. May come from a different provider than the cheapest input.
$0.60Azure$0.15Venice
$60.00OpenAI list price$13.50Venice · int4
Benchmarks
BullshitBench v2Nonsense detection — Given a confidently-worded but nonsensical prompt, does the AI spot that it makes no sense and push back — instead of playing along and inventing an answer? The score is how often it clearly called out the nonsense. Higher is better.
2%12%
GPQA DiamondScience — Graduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better.
40.2%80.1%
Overview
CompanyOpenAIOpenAI
Release dateJul 18 2024Aug 5 2025
AccessClosedOpen Weight
Model detailsView modelView model

Frequently asked questions

gpt-oss-120b leads GPT-4o mini on 2 of the 2 benchmarks they both report (BullshitBench v2, GPQA Diamond). Only GPT-4o mini has a verified first-party API price: $0.15 per million input tokens and $0.60 per million output tokens. No pay-as-you-go API rate is tracked for gpt-oss-120b. GPT-4o mini shipped 383 days before gpt-oss-120b, so benchmark comparisons should account for the intervening progress.

Context windows are 128k (GPT-4o mini) vs 128k (gpt-oss-120b). GPT-4o mini is closed, while gpt-oss-120b is open weight.

On BullshitBench v2, gpt-oss-120b leads at 12% vs GPT-4o mini at 2%. On GPQA Diamond, gpt-oss-120b leads at 80.1% vs GPT-4o mini at 40.2%.