Compare AI models

Specifications
Context windowHow much information the model can work with in one request, measured in tokens — pieces of words or other data. This includes your question, attachments, conversation and reply. Limits can vary by model variant and provider.
1M400k
API pricingUSD per 1M tokens · lower wins · base tier
Input priceWhat you pay for everything you send the model — your question, plus any documents or earlier conversation you include with it.
$0.10$0.20
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.
$0.50$1.25
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.
$0.004$0.02
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.
—$0.10OpenAI
Cheapest outputLowest output rate across every provider on OpenRouter, the lab included. May come from a different provider than the cheapest input.
—$0.625OpenAI
$45.00Meta list price$103OpenAI list price
These models have no shared benchmark scores.
Overview
CompanyMetaOpenAI
Release dateNov 9 2026Mar 17 2026
AccessClosedClosed
Model detailsView modelView model

Frequently asked questions

Muse Ember and GPT-5.4 nano don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Muse Ember is cheaper on both input and output: $0.10 vs $0.20 per million input tokens, and $0.50 vs $1.25 per million output tokens. Figures are base-tier rates. GPT-5.4 nano shipped 237 days before Muse Ember, so benchmark comparisons should account for the intervening progress.

Context windows are 1M (Muse Ember) vs 400k (GPT-5.4 nano).

Direct benchmark comparisons are unavailable — Muse Ember and GPT-5.4 nano don't publish scores on any of the same benchmarks.