Mistral Medium 3.5vsGrok 4.20 Beta

Mistral Medium 3.5
Grok 4.20 Beta
Specifications
Parameters
128B
Context window
256k
API pricing
Input price
$1.50$1.25
Output price
$7.50$2.50
Cached input price
$0.20
Benchmarks
SWE-Bench Verified
77.6%76.7%
Benchmarks
BullshitBench v2
56%
ARC-AGI-2
53.3%
Overview
CompanyMistralSpaceXAI
Release dateApr 29 2026Feb 17 2026
AccessOpen WeightProprietary

Other comparisons

Mistral Medium 3.5vsClaude Fable 5.1Grok 4.20 BetavsClaude Fable 5.1Mistral Medium 3.5vsGPT-6 AstraGrok 4.20 BetavsGPT-6 AstraMistral Medium 3.5vsGemini 3.8 FlashGrok 4.20 BetavsGemini 3.8 FlashMistral Medium 3.5vsMuse Spark 1.3Grok 4.20 BetavsMuse Spark 1.3Mistral Medium 3.5vsDeepSeek-V4.1-FlashGrok 4.20 BetavsDeepSeek-V4.1-FlashMistral Medium 3.5vsKimi K3Grok 4.20 BetavsKimi K3

Frequently asked questions

Mistral Medium 3.5 leads Grok 4.20 Beta on 1 of the 1 benchmark they both report (SWE-Bench Verified). Grok 4.20 Beta is cheaper on both input and output: $1.25 vs $1.50 per million input tokens, and $2.50 vs $7.50 per million output tokens. Figures are base-tier rates. Grok 4.20 Beta shipped 71 days before Mistral Medium 3.5, so benchmark comparisons should account for the intervening progress.

Mistral Medium 3.5 is open weight, while Grok 4.20 Beta is proprietary.

On SWE-Bench Verified, Mistral Medium 3.5 leads at 77.6% vs Grok 4.20 Beta at 76.7%.