Claude Opus 5.5 vs MiniMax M3

Anthropic · US  |  MiniMax · China · Updated June 2026

Quick verdict

Pick Claude Opus 5.5 for performs at roughly claude fable 5.1's level on most work, at 40% lower typical workload cost than opus 5 or anthropic reports it surpasses fable 5.1 on agentic coding, knowledge work, computer use, visual chart recognition, and multidisciplinary reasoning. Pick MiniMax M3 for open-weight 428b moe (~23b active per token) with a 1m-token context or native multimodal input — text, image and video. Choose MiniMax M3 if you need self-hosting or data privacy; Claude Opus 5.5 if you want a managed API.

Claude Opus 5.5 (Anthropic, US) and MiniMax M3 (MiniMax, China) line up two different AI ecosystems against each other — a comparison that is as much about cost philosophy and openness as raw capability. Claude Opus 5.5 is anthropic's September 22, 2026 update: Fable 5.1-level performance at 40% lower cost than Opus 5, with faster output and cheaper caching. MiniMax M3 is miniMax's open-weight 428B multimodal model with a 1M context — strong reported coding (59.0 SWE-Bench Pro) at low entry pricing. 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 Opus 5.5MiniMax M3
ProviderAnthropic (US) MiniMax (China)
ReleasedSeptember 22, 2026 May 31, 2026
Context window1M tokens (~1,500 pages) 1M (~1,573 pages)
Price (in/out)$4/$20 per 1M tokens $0.23/$0.96 per 1M tokens
Open weight?No — API only Yes — self-hostable
Modalitiestext, image, code text, image, video, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Performs at roughly Claude Fable 5.1's level on most work, at 40% lower typical workload cost than Opus 5

Claude Opus 5.5

Anthropic's September 22, 2026 update: Fable 5.1-level performance at 40% lower cost than Opus 5, with faster output and cheaper caching — and it is the newer of the two.

Anthropic reports it surpasses Fable 5.1 on agentic coding, knowledge work, computer use, visual chart recognition, and multidisciplinary reasoning

Claude Opus 5.5

Claude Opus 5.5 lists anthropic reports it surpasses Fable 5.1 on agentic coding, knowledge work, computer use, visual chart recognition, and multidisciplinary reasoning among its strengths; MiniMax M3 does not.

Pricing cut to $4/$20 per million tokens (20% below Opus 5's $5/$25), cache reads down 60% to $0.20/MTok

Claude Opus 5.5

MiniMax M3 is comparatively weak here — price doubles to $0.60/$2.40 above 512K tokens — not flat across 1M

Open-weight 428B MoE (~23B active per token) with a 1M-token context

MiniMax M3

Open weights make this possible at all — Claude Opus 5.5 is API-only, so it cannot leave the vendor's servers.

Native multimodal input — text, image and video

MiniMax M3

MiniMax's open-weight 428B multimodal model with a 1M context — strong reported coding (59.0 SWE-Bench Pro) at low entry pricing — and it runs cheaper at $0.23/$0.96 per 1M tokens.

Reports 59.0 on SWE-Bench Pro (a strong open-weight score), surpassing GPT-5.5

MiniMax M3

MiniMax's open-weight 428B multimodal model with a 1M context — strong reported coding (59.0 SWE-Bench Pro) at low entry pricing — and its weights are open while Claude Opus 5.5 is API-only.

Lowest cost at scale

MiniMax M3

At $0.23/$0.96 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Which should you pick?

A cost-sensitive startup shipping high volume

MiniMax M3

At $0.23/$0.96 per 1M tokens it undercuts Claude Opus 5.5, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

MiniMax M3

Larger 1M window fits more in one prompt.

A team with data-privacy or self-hosting needs

MiniMax M3

Open weights let you run it on your own hardware; Claude Opus 5.5 is API-only.

Anyone whose priority is performs at roughly claude fable 5.1's level on most work, at 40% lower typical workload cost than opus 5

Claude Opus 5.5

It is specifically built for that.

Anyone whose priority is open-weight 428b moe (~23b active per token) with a 1m-token context

MiniMax M3

That is its strongest area.

An enterprise with regional data-residency rules

Claude Opus 5.5 or MiniMax M3

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

Claude Opus 5.5: where it fits

Anthropic's September 22, 2026 update: Fable 5.1-level performance at 40% lower cost than Opus 5, with faster output and cheaper caching. Released September 22, 2026 by Anthropic, it is built for performs at roughly Claude Fable 5.1's level on most work, at 40% lower typical workload cost than Opus 5, anthropic reports it surpasses Fable 5.1 on agentic coding, knowledge work, computer use, visual chart recognition, and multidisciplinary reasoning, pricing cut to $4/$20 per million tokens (20% below Opus 5's $5/$25), cache reads down 60% to $0.20/MTok, and output speed increased over 30% versus Opus 5.

Its trade-offs are real: not a reasoning-ceiling upgrade over Fable 5.1 — pitched as matching its performance at lower cost, not beating it outright, like Opus 5, the headline 1M-token context is not uniformly available across every platform and plan — some API paths default to a smaller window, and first model in the 5.5 line; Anthropic has signaled Sonnet 5.5 and Haiku 5.5 are still weeks away, so the lower tiers of the family aren't out yet. At $4 in / $20 out per million tokens, it sits in the mid price band.

MiniMax M3: where it fits

MiniMax's open-weight 428B multimodal model with a 1M context — strong reported coding (59.0 SWE-Bench Pro) at low entry pricing. Released May 31, 2026 by MiniMax, it is built for open-weight 428B MoE (~23B active per token) with a 1M-token context, native multimodal input — text, image and video, reports 59.0 on SWE-Bench Pro (a strong open-weight score), surpassing GPT-5.5, and low entry pricing at $0.30/$1.20 per million up to 512K tokens.

Its trade-offs: price doubles to $0.60/$2.40 above 512K tokens — not flat across 1M, miniMax's own reported 80.5 SWE-Bench Verified figure is vendor-stated, not independently verified, sWE-Bench Pro is a different, harder benchmark than SWE-Bench Verified, and newer than M2.7 but with less independent testing so far. At $0.23 in / $0.96 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

The defining split here is open vs. closed. MiniMax M3 gives you weights you control — self-host it, fine-tune it, keep data in-house, pay only for hardware. Claude Opus 5.5 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 Opus 5.5 and MiniMax M3 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 Opus 5.5 or MiniMax M3 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, Claude Opus 5.5 leans toward performs at roughly claude fable 5.1's level on most work, at 40% lower typical workload cost than opus 5 while MiniMax M3 leans toward open-weight 428b moe (~23b active per token) with a 1m-token context, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Claude Opus 5.5 or MiniMax M3?

MiniMax M3 is open-weight, so self-hosting means no per-token fee (you pay for hardware instead), while Claude Opus 5.5 is API-metered at $4/$20 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?

Effectively neither — 1M tokens vs 1M is a difference of a few percent. Remember advertised ≠ usable: recall typically degrades before the ceiling.

Can I use both Claude Opus 5.5 and MiniMax M3 together?

Yes — a multi-model platform like LumiChats gives you Claude Opus 5.5, MiniMax M3 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 Opus 5.5 or MiniMax M3?

Claude Opus 5.5 — released September 22, 2026, about 4 months after MiniMax M3.

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.