Claude Haiku 4.5 vs Mistral Medium 3.5

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

Quick verdict

Pick Claude Haiku 4.5 for fastest claude model or near-frontier coding for its tier — 73.3% on swe-bench verified. 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; Claude Haiku 4.5 if you want a managed API.

Claude Haiku 4.5 (Anthropic, 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. Claude Haiku 4.5 is anthropic's fastest, most compact model — built for speed and volume. 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

SpecClaude Haiku 4.5Mistral Medium 3.5
ProviderAnthropic (US) Mistral AI (France)
ReleasedOctober 15, 2025 April 29, 2026
Context window200K (~300 pages) 256K (~384 pages)
Price (in/out)$1/$5 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 Verified73.3% Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Fastest Claude model

Claude Haiku 4.5

Anthropic's fastest, most compact model — built for speed and volume — and it runs cheaper at $1/$5 per 1M tokens.

Near-frontier coding for its tier — 73.3% on SWE-Bench Verified

Claude Haiku 4.5

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

Low-latency, high-volume API calls

Claude Haiku 4.5

At $1/$5 per 1M tokens it undercuts Mistral Medium 3.5 ($1.5/$7.5 per 1M tokens), and that gap compounds at volume.

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

Mistral Medium 3.5

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) — and it carries the larger 256K context.

128B dense open-weight model — self-hostable

Mistral Medium 3.5

Open weights make this possible at all — Claude Haiku 4.5 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

Claude Haiku 4.5 is comparatively weak here — not for deep reasoning

Lowest cost at scale

Claude Haiku 4.5

At $1/$5 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

Mistral Medium 3.5

Its 256K window is about 1.3× larger than Claude Haiku 4.5's 200K, fitting roughly 384 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

Claude Haiku 4.5

At $1/$5 per 1M tokens it undercuts Mistral Medium 3.5, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Mistral Medium 3.5

Larger 256K 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; Claude Haiku 4.5 is API-only.

Anyone whose priority is fastest claude model

Claude Haiku 4.5

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

Claude Haiku 4.5 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.

Claude Haiku 4.5: where it fits

Anthropic's fastest, most compact model — built for speed and volume. Released October 15, 2025 by Anthropic, it is built for fastest Claude model, near-frontier coding for its tier — 73.3% on SWE-Bench Verified, low-latency, high-volume API calls, and cheapest Claude tier at $1/$5.

Its trade-offs are real: smallest context in the family (200K), and not for deep reasoning. At $1 in / $5 out per million tokens, it sits in the budget 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. Claude Haiku 4.5 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 Claude Haiku 4.5 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 Claude Haiku 4.5 or Mistral Medium 3.5 better for coding?

Public SWE-Bench figures are not available for Mistral Medium 3.5, so the honest test is your own repository — run an identical real bug through both. By design, Claude Haiku 4.5 leans toward fastest claude model 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, Claude Haiku 4.5 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 Claude Haiku 4.5 is API-metered at $1/$5 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?

Mistral Medium 3.5 — 256K vs 200K, about 1.3× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both Claude Haiku 4.5 and Mistral Medium 3.5 together?

Yes — a multi-model platform like LumiChats gives you Claude Haiku 4.5, 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, Claude Haiku 4.5 or Mistral Medium 3.5?

Mistral Medium 3.5 — released April 29, 2026, about 7 months after Claude Haiku 4.5.

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.