Mistral Large 4 enters preview with 1 trillion parameters, open weights due this month

What launched

Mistral AI released Mistral Large 4 as a public preview on its API on 6 October 2026.¹ Mistral describes it as a mixture-of-experts model with 1 trillion total parameters and 52 billion active parameters.¹ Some coverage cites 49 billion active parameters from launch material, but Mistral's own page says 52 billion.¹²

Mistral says the model was trained from scratch on 3,800 NVIDIA Grace Blackwell GPUs in its own European data centres, and that it is fluent in more than 160 languages.¹

Price

Mistral lists the preview at $1.36 per million input tokens and $4.18 per million output tokens.¹ eWeek reports a two-week launch discount to $0.68 and $2.09, and notes that the list prices are well above Mistral Large 3's $0.50 and $1.50.²

Open weights

Mistral says downloadable weights are due by the end of October.¹ VentureBeat reports a target date of 27 October and an expected custom Mistral licence.³ Mistral's announcement does not state the licence.

The benchmark claims

Mistral reports 61.7% on DeepSWE v1.1 and 49.8% on a Coding Agent Index, among other scores.² These are the company's own numbers. VentureBeat notes that several other models score higher on the live DeepSWE leaderboard, and that Large 4 was not yet listed on independent leaderboards when it reported.³

What it means for developers

The preview is available through Mistral's developer console. Teams already on Mistral Large 3 should compare the higher list price against their workloads before switching, and watch for the open-weights licence if they want to self-host.