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.
200k256k
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.
—$1.00
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.
—$2.00
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.
—$0.20
—$300SpaceXSI list price
These models have no shared benchmark scores.
Overview
CompanyAnthropicSpaceXSI
Release dateMar 4 2024Aug 28 2025
AccessClosedClosed
Model detailsView modelView model

Frequently asked questions

Claude 3 Sonnet and Grok Code Fast 1 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Only Grok Code Fast 1 has a verified first-party API price: $1.00 per million input tokens and $2.00 per million output tokens. No pay-as-you-go API rate is tracked for Claude 3 Sonnet. Claude 3 Sonnet shipped 542 days before Grok Code Fast 1, so benchmark comparisons should account for the intervening progress.

Context windows are 200k (Claude 3 Sonnet) vs 256k (Grok Code Fast 1).

Direct benchmark comparisons are unavailable — Claude 3 Sonnet and Grok Code Fast 1 don't publish scores on any of the same benchmarks.