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.
$1.75—
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.
$14.00—
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.
$0.175—
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.
$1.75Azure$0.0193OpenInference
Cheapest outputLowest output rate across every provider on OpenRouter, the lab included. May come from a different provider than the cheapest input.
$14.00Azure$0.145StreamLake
$1,050OpenAI list price$15.95StreamLake · fp8
Benchmarks
threejsevalCommunity preference (Three.js) — Every model gets the same prompt — "the Eiffel Tower", "a glass fishbowl", "a robot arm picking toys into a box" — and builds a 3D scene in Three.js. Real people then see two scenes side by side, names hidden, and vote for the one they prefer. The votes become a chess-style Elo rating on threejseval.com, averaged across all the prompts. It measures whether the scene looks and moves right to a human eye, not whether the code passes a test. Higher is better.
11711390
Overview
CompanyOpenAIZ.ai
Release dateFeb 5 2026Aug 26 2026
AccessClosedOpen Weight
Model detailsView modelView model

Frequently asked questions

GLM-5.3-Flash leads GPT-5.3-Codex on 1 of the 1 benchmark they both report (threejseval). Only GPT-5.3-Codex has a verified first-party API price: $1.75 per million input tokens and $14.00 per million output tokens. No pay-as-you-go API rate is tracked for GLM-5.3-Flash. GPT-5.3-Codex shipped 202 days before GLM-5.3-Flash, so benchmark comparisons should account for the intervening progress.

GPT-5.3-Codex is closed, while GLM-5.3-Flash is open weight.

On threejseval, GLM-5.3-Flash leads at 1390 vs GPT-5.3-Codex at 1171.