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.
$5.00—
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.
$25.00—
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.
$0.50—
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.
$5.00Amazon Bedrock$0.036OpenInference
Cheapest outputLowest output rate across every provider on OpenRouter, the lab included. May come from a different provider than the cheapest input.
$25.00Amazon Bedrock$0.145StreamLake
$2,250Anthropic list price$15.95StreamLake · fp8
Benchmarks
Humanity's Last Exam · with toolsMultidisciplinary reasoning — Humanity's Last Exam — extremely hard expert questions across many subjects. “With tools” means the AI is allowed to search the web or run code while answering. Higher is better.
30.8%55.3%
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.
11531390
Overview
CompanyAnthropicZ.ai
Release dateNov 24 2025Aug 26 2026
AccessClosedOpen Weight
Model detailsView modelView model

Frequently asked questions

GLM-5.3-Flash leads Claude Opus 4.5 on 2 of the 2 benchmarks they both report (Humanity's Last Exam, threejseval). Only Claude Opus 4.5 has a verified first-party API price: $5.00 per million input tokens and $25.00 per million output tokens. No pay-as-you-go API rate is tracked for GLM-5.3-Flash. Claude Opus 4.5 shipped 275 days before GLM-5.3-Flash, so benchmark comparisons should account for the intervening progress.

Claude Opus 4.5 is closed, while GLM-5.3-Flash is open weight.

On Humanity's Last Exam · with tools, GLM-5.3-Flash leads at 55.3% vs Claude Opus 4.5 at 30.8%. On threejseval, GLM-5.3-Flash leads at 1390 vs Claude Opus 4.5 at 1153.