Claude Sonnet 5.5 vs MiniMax M3

Anthropic · US  |  MiniMax · China · Updated June 2026

Quick verdict

Pick Claude Sonnet 5.5 for terminal-bench 4.0 agentic coding jumps to 70.6%, up from claude sonnet 5's 10.3% or same $2/$10 per million token pricing as sonnet 5, with cache-read price cut 50% to $0.10/mtok as of october 7, 2026. 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 Sonnet 5.5 if you want a managed API.

Claude Sonnet 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 Sonnet 5.5 is anthropic's September 28, 2026 mid-tier update — same $2/$10 pricing as Sonnet 5 but a large agentic-coding jump (Terminal-Bench 4.0: 70.6% vs 10.3%). 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 Sonnet 5.5MiniMax M3
ProviderAnthropic (US) MiniMax (China)
ReleasedSeptember 28, 2026 May 31, 2026
Context window1M tokens (~1,500 pages) 1M (~1,573 pages)
Price (in/out)$2/$10 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

Terminal-Bench 4.0 agentic coding jumps to 70.6%, up from Claude Sonnet 5's 10.3%

Claude Sonnet 5.5

MiniMax M3 is comparatively weak here — miniMax's own reported 80.5 SWE-Bench Verified figure is vendor-stated, not independently verified

Same $2/$10 per million token pricing as Sonnet 5, with cache-read price cut 50% to $0.10/MTok as of October 7, 2026

Claude Sonnet 5.5

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

Scores close to Opus 5.5 on several benchmarks (e.g. GDPval-AA v2.1 knowledge-work Elo) at a fraction of the cost

Claude Sonnet 5.5

Anthropic's September 28, 2026 mid-tier update — same $2/$10 pricing as Sonnet 5 but a large agentic-coding jump (Terminal-Bench 4.0: 70.6% vs 10.3%) — and it is the newer of the two.

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

MiniMax M3

Open weights make this possible at all — Claude Sonnet 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

Claude Sonnet 5.5 is comparatively weak here — anthropic is explicit that Opus 5.5 'remains clearly stronger' on complex, open-ended work requiring sustained judgment

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 Sonnet 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 Sonnet 5.5 is API-only.

Anyone whose priority is terminal-bench 4.0 agentic coding jumps to 70.6%, up from claude sonnet 5's 10.3%

→ Claude Sonnet 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 Sonnet 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 Sonnet 5.5: where it fits

Anthropic's September 28, 2026 mid-tier update — same $2/$10 pricing as Sonnet 5 but a large agentic-coding jump (Terminal-Bench 4.0: 70.6% vs 10.3%). Released September 28, 2026 by Anthropic, it is built for terminal-Bench 4.0 agentic coding jumps to 70.6%, up from Claude Sonnet 5's 10.3%, same $2/$10 per million token pricing as Sonnet 5, with cache-read price cut 50% to $0.10/MTok as of October 7, 2026, scores close to Opus 5.5 on several benchmarks (e.g. GDPval-AA v2.1 knowledge-work Elo) at a fraction of the cost, and anthropic highlights stronger document/slide generation, spreadsheet work, and visual chart recognition (Chartography: 61.6%).

Its trade-offs are real: anthropic is explicit that Opus 5.5 'remains clearly stronger' on complex, open-ended work requiring sustained judgment, 1M-token context isn't uniformly available across every platform/plan, consistent with the rest of the 5.5 family, and mid-tier update released a week after Opus 5.5 (Sept 22) — Haiku 5.5 followed Oct 7 to complete the family. At $2 in / $10 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 Sonnet 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 Sonnet 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 Sonnet 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 Sonnet 5.5 leans toward terminal-bench 4.0 agentic coding jumps to 70.6%, up from claude sonnet 5's 10.3% 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 Sonnet 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 Sonnet 5.5 is API-metered at $2/$10 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 Sonnet 5.5 and MiniMax M3 together?

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

Claude Sonnet 5.5 — released September 28, 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.