Grok 4.20 Multi-Agent: pricing, context and benchmarks

What you need to know about Grok 4.20 Multi-Agent

xAI, based in United States, put Grok 4.20 Multi-Agent online on March 31, 2026. It accepts text, images, and files as input and produces text. Its context window reaches 2,000,000 tokens, larger than 100 % of the models in the registry, and it can write up to 1,800,000 tokens in one go.

It has been available for about 7 months, long enough for its prices and scores to have settled.

Grok 4.20 Multi-Agent pricing

On OpenRouter, Grok 4.20 Multi-Agent costs $1.25 per million input tokens and $2.5 per million output tokens. Counting three tokens read for every token written, its average price is $1.563 per million, more expensive than 67 % of paid models (2 times the median of $0.76).

A concrete example: a task that sends 2,000 tokens (about 1,500 words) and receives a 500-token answer costs $0.0038. At 1,000 tasks a day, budget $113 a month. The price calculator redoes this with your own volumes.

Tokens already sent and cached are billed at $0.2 per million.

Performance and benchmarks

Epoch AI does not yet publish a capabilities index for Grok 4.20 Multi-Agent. We therefore show no made-up performance rating: only price, context and features count towards its score.

Features, privacy and local use

• It does not support tool calling: it is not suited to driving an AI agent that has to act.
• It can answer in an enforced JSON format (structured outputs).
• It is a reasoning model: it "thinks" before answering, which helps on hard tasks but uses more output tokens.
• Its knowledge stops at September 2025.

Its weights are not published: it can only be used through the xAI API or a broker such as OpenRouter, which means sending your data off your machines.

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