Grok 4.6 vs Mistral Medium 3.5

xAI · US  |  Mistral AI · France · Updated June 2026

Quick verdict

Pick Grok 4.6 for frontier-tier intelligence at a value price - artificial analysis intelligence index 61, tying gpt-5.6 sol or ranked #2 on artificial analysis's independent gdpval agentic test, behind only claude opus 5. Pick Mistral Medium 3.5 for strong intelligence-for-size — artificial analysis intelligence index 30, near the top of its price tier or 128b dense open-weight model — self-hostable. Choose Mistral Medium 3.5 if you need self-hosting or data privacy; Grok 4.6 if you want a managed API.

Grok 4.6 (xAI, US) and Mistral Medium 3.5 (Mistral AI, France) line up two different AI ecosystems against each other — a comparison that is as much about cost philosophy and openness as raw capability. Grok 4.6 is xAI's Grok 4.6 - frontier-level intelligence (AA Index 61, tying GPT-5.6 Sol) at a fraction of flagship pricing, and already in Cursor and Copilot. Mistral Medium 3.5 is mistral's efficient 128B open-weight model — a single dense model unifying reasoning and coding that punches above its size on independent tests (AA Index 30). They diverge most on price, context window and open vs. closed weights — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecGrok 4.6Mistral Medium 3.5
ProviderxAI (US) Mistral AI (France)
ReleasedAugust 12, 2026 April 29, 2026
Context window500K (~750 pages) 256K (~384 pages)
Price (in/out)$2/$6 per 1M tokens $1.5/$7.5 per 1M tokens
Open weight?No — API only Yes — self-hostable
Modalitiestext, image, code text, image, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Frontier-tier intelligence at a value price - Artificial Analysis Intelligence Index 61, tying GPT-5.6 Sol

Grok 4.6

Mistral Medium 3.5 is comparatively weak here — below the absolute frontier — a value/efficiency pick, not a flagship-beater

Ranked #2 on Artificial Analysis's independent GDPval agentic test, behind only Claude Opus 5

Grok 4.6

XAI's Grok 4.6 - frontier-level intelligence (AA Index 61, tying GPT-5.6 Sol) at a fraction of flagship pricing, and already in Cursor and Copilot — and it carries the larger 500K context.

$2/$6 per million tokens - a fraction of Claude Opus 5 or GPT-5.6 Sol

Grok 4.6

Its 500K window holds about 2× more than Mistral Medium 3.5's 256K in a single prompt.

Strong intelligence-for-size — Artificial Analysis Intelligence Index 30, near the top of its price tier

Mistral Medium 3.5

At $1.5/$7.5 per 1M tokens it undercuts Grok 4.6 ($2/$6 per 1M tokens), and that gap compounds at volume.

128B dense open-weight model — self-hostable

Mistral Medium 3.5

Open weights make this possible at all — Grok 4.6 is API-only, so it cannot leave the vendor's servers.

Unifies reasoning and coding into one model with an adjustable reasoning effort

Mistral Medium 3.5

Grok 4.6 is comparatively weak here — coding gains (DeepSWE 65.9, APEX-Agents 57.5) are xAI's own numbers, not independently reproduced

Lowest cost at scale

Mistral Medium 3.5

At $1.5/$7.5 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

Grok 4.6

Its 500K window is about 2× larger than Mistral Medium 3.5's 256K, fitting roughly 750 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

Mistral Medium 3.5

At $1.5/$7.5 per 1M tokens it undercuts Grok 4.6, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Grok 4.6

Larger 500K window fits more in one prompt.

A team with data-privacy or self-hosting needs

Mistral Medium 3.5

Open weights let you run it on your own hardware; Grok 4.6 is API-only.

Anyone whose priority is frontier-tier intelligence at a value price - artificial analysis intelligence index 61, tying gpt-5.6 sol

Grok 4.6

It is specifically built for that.

Anyone whose priority is strong intelligence-for-size — artificial analysis intelligence index 30, near the top of its price tier

Mistral Medium 3.5

That is its strongest area.

An enterprise with regional data-residency rules

Grok 4.6 or Mistral Medium 3.5

Origin (US vs France) affects where data is processed and which compliance regime applies — check the provider's terms for your region.

Grok 4.6: where it fits

XAI's Grok 4.6 - frontier-level intelligence (AA Index 61, tying GPT-5.6 Sol) at a fraction of flagship pricing, and already in Cursor and Copilot. Released August 12, 2026 by xAI, it is built for frontier-tier intelligence at a value price - Artificial Analysis Intelligence Index 61, tying GPT-5.6 Sol, ranked #2 on Artificial Analysis's independent GDPval agentic test, behind only Claude Opus 5, $2/$6 per million tokens - a fraction of Claude Opus 5 or GPT-5.6 Sol, and 500K-token context; available same-day in Cursor and (two days later) GitHub Copilot.

Its trade-offs are real: coding gains (DeepSWE 65.9, APEX-Agents 57.5) are xAI's own numbers, not independently reproduced, parameter count is undisclosed, text and image input only - not a full multimodal model, and fast-moving target: xAI says Grok 4.7 is only weeks away. At $2 in / $6 out per million tokens, it sits in the mid price band.

Mistral Medium 3.5: where it fits

Mistral's efficient 128B open-weight model — a single dense model unifying reasoning and coding that punches above its size on independent tests (AA Index 30). Released April 29, 2026 by Mistral AI, it is built for strong intelligence-for-size — Artificial Analysis Intelligence Index 30, near the top of its price tier, 128B dense open-weight model — self-hostable, unifies reasoning and coding into one model with an adjustable reasoning effort, and 256K context with text and image input.

Its trade-offs: below the absolute frontier — a value/efficiency pick, not a flagship-beater, output pricing ($7.50/M) is higher than the cheapest Chinese rivals, license framing ('open' vs enterprise) varies across sources — confirm terms for commercial use, and no native video or audio. At $1.5 in / $7.5 out per million tokens, it sits in the mid price band.

The bottom line for this matchup

The defining split here is open vs. closed. Mistral Medium 3.5 gives you weights you control — self-host it, fine-tune it, keep data in-house, pay only for hardware. Grok 4.6 gives you a managed, always-updated API with no infrastructure to run. Teams with GPUs, privacy requirements, or huge volume often favour the open model; teams that want zero ops and the latest capabilities favour the closed one. Capability is close enough that this operational question, not the benchmark, usually decides it.

Want both Grok 4.6 and Mistral Medium 3.5 without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is Grok 4.6 or Mistral Medium 3.5 better for coding?

Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, Grok 4.6 leans toward frontier-tier intelligence at a value price - artificial analysis intelligence index 61, tying gpt-5.6 sol while Mistral Medium 3.5 leans toward strong intelligence-for-size — artificial analysis intelligence index 30, near the top of its price tier, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Grok 4.6 or Mistral Medium 3.5?

Mistral Medium 3.5 is open-weight, so self-hosting means no per-token fee (you pay for hardware instead), while Grok 4.6 is API-metered at $2/$6 per 1M tokens. For most teams without GPUs, the API model is cheaper to start; at very high volume, self-hosting can win.

Which has the bigger context window?

Grok 4.6 — 500K vs 256K, about 2× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both Grok 4.6 and Mistral Medium 3.5 together?

Yes — a multi-model platform like LumiChats gives you Grok 4.6, Mistral Medium 3.5 and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, Grok 4.6 or Mistral Medium 3.5?

Grok 4.6 — released August 12, 2026, about 4 months after Mistral Medium 3.5.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.