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.
—320B
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.
—1M
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.
$20.00—
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.
$80.00—
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.
$20.00OpenAI$0.048OpenInference
Cheapest outputLowest output rate across every provider on OpenRouter, the lab included. May come from a different provider than the cheapest input.
$80.00OpenAI$0.20OpenInference
$8,000OpenAI list price$19.60OpenInference · fp4
These models have no shared benchmark scores.
Overview
CompanyOpenAIZ.ai
Release dateJun 10 2025Aug 26 2026
AccessClosedOpen Weight
Model detailsView modelView model

Frequently asked questions

o3-pro and GLM-5.3-Flash don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Only o3-pro has a verified first-party API price: $20.00 per million input tokens and $80.00 per million output tokens. No pay-as-you-go API rate is tracked for GLM-5.3-Flash. o3-pro shipped 442 days before GLM-5.3-Flash, so benchmark comparisons should account for the intervening progress.

o3-pro is closed, while GLM-5.3-Flash is open weight.

Direct benchmark comparisons are unavailable — o3-pro and GLM-5.3-Flash don't publish scores on any of the same benchmarks.