Claude Sonnet 4.5 vs Qwen 3.6 Plus

Anthropic · US  |  Alibaba · China · Updated June 2026

Quick verdict

Pick Claude Sonnet 4.5 for agentic coding — 77.2% on swe-bench verified, the best score any model had posted at its launch or computer use and gui automation (61.4% osworld at launch). Pick Qwen 3.6 Plus for strong gpqa diamond science reasoning or open-weight and budget-friendly. On a tight budget at scale, Qwen 3.6 Plus is the value pick.

Claude Sonnet 4.5 (Anthropic, US) and Qwen 3.6 Plus (Alibaba, 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 Claude Sonnet 4.5 is september 2025's coding state of the art at $3/$15 — still supported, but 200K-capped and twice superseded. Qwen 3.6 Plus is alibaba's open-weight contender — surprising benchmark wins at a budget price. They diverge most on price, context window and coding benchmarks — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecClaude Sonnet 4.5Qwen 3.6 Plus
ProviderAnthropic (US) Alibaba (China)
ReleasedSeptember 29, 2025 March 31, 2026
Context window200K (~300 pages) 1M (~1,500 pages)
Price (in/out)$3/$15 per 1M tokens $0.325/$1.95 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image, code text, image, code
SWE-Bench Verified77.2% 78.8%
MRCR v2 @ 1MNot published Not published

Who wins what

Agentic coding — 77.2% on SWE-Bench Verified, the best score any model had posted at its launch

Claude Sonnet 4.5

Qwen 3.6 Plus is comparatively weak here — benchmark coverage still maturing

Computer use and GUI automation (61.4% OSWorld at launch)

Claude Sonnet 4.5

Claude Sonnet 4.5 lists computer use and GUI automation (61.4% OSWorld at launch) among its strengths; Qwen 3.6 Plus does not.

Long-horizon autonomy — Anthropic reported 30+ hours of sustained focus on multi-step tasks

Claude Sonnet 4.5

Claude Sonnet 4.5 lists long-horizon autonomy — Anthropic reported 30+ hours of sustained focus on multi-step tasks among its strengths; Qwen 3.6 Plus does not.

Strong GPQA Diamond science reasoning

Qwen 3.6 Plus

Alibaba's open-weight contender — surprising benchmark wins at a budget price — and it leads SWE-Bench Verified 78.8% to 77.2%.

Open-weight and budget-friendly

Qwen 3.6 Plus

At $0.325/$1.95 per 1M tokens it undercuts Claude Sonnet 4.5 ($3/$15 per 1M tokens), and that gap compounds at volume.

1M context

Qwen 3.6 Plus

Its 1M window holds about 5× more than Claude Sonnet 4.5's 200K in a single prompt.

Lowest cost at scale

Qwen 3.6 Plus

At $0.325/$1.95 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

Qwen 3.6 Plus

Its 1M window is about 5× larger than Claude Sonnet 4.5's 200K, fitting roughly 1,500 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

Qwen 3.6 Plus

At $0.325/$1.95 per 1M tokens it undercuts Claude Sonnet 4.5, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Qwen 3.6 Plus

Larger 1M window fits more in one prompt.

Anyone whose priority is agentic coding — 77.2% on swe-bench verified, the best score any model had posted at its launch

Claude Sonnet 4.5

It is specifically built for that.

Anyone whose priority is strong gpqa diamond science reasoning

Qwen 3.6 Plus

That is its strongest area.

An enterprise with regional data-residency rules

Claude Sonnet 4.5 or Qwen 3.6 Plus

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

Claude Sonnet 4.5: where it fits

September 2025's coding state of the art at $3/$15 — still supported, but 200K-capped and twice superseded. Released September 29, 2025 by Anthropic, it is built for agentic coding — 77.2% on SWE-Bench Verified, the best score any model had posted at its launch, computer use and GUI automation (61.4% OSWorld at launch), long-horizon autonomy — Anthropic reported 30+ hours of sustained focus on multi-step tasks, and tracking its own remaining token budget natively, which few models do.

Its trade-offs are real: superseded twice — Sonnet 4.6 and Sonnet 5 match or beat it at the same or lower price, capped at 200K since Anthropic retired its 1M beta in April 2026, while its successors ship 1M as standard, and missing the modern API surface: no adaptive thinking, no effort control, and half the max output of newer Sonnets. At $3 in / $15 out per million tokens, it sits in the mid price band.

Qwen 3.6 Plus: where it fits

Alibaba's open-weight contender — surprising benchmark wins at a budget price. Released March 31, 2026 by Alibaba, it is built for strong GPQA Diamond science reasoning, open-weight and budget-friendly, 1M context, and multilingual coverage.

Its trade-offs: less Western ecosystem tooling, and benchmark coverage still maturing. At $0.325 in / $1.95 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

This is less "which is smarter" and more "which ecosystem fits." Claude Sonnet 4.5 (US) and Qwen 3.6 Plus (China) differ on pricing philosophy, data-residency, and tooling as much as on raw scores. Qwen 3.6 Plus is the cheaper option, which matters at volume. The pragmatic move is to run one real task through both and judge the outputs against your own constraints — including where your data is allowed to be processed.

Want both Claude Sonnet 4.5 and Qwen 3.6 Plus 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 4.5 or Qwen 3.6 Plus better for coding?

On SWE-Bench Verified, Claude Sonnet 4.5 scores 77.2% and Qwen 3.6 Plus scores 78.8% — effectively a tie, so pick on price and ecosystem.

Which is cheaper, Claude Sonnet 4.5 or Qwen 3.6 Plus?

Qwen 3.6 Plus is cheaper — $3/$15 per 1M tokens vs $0.325/$1.95 per 1M tokens, roughly 9.2× apart on input.

Which has the bigger context window?

Qwen 3.6 Plus — 1M vs 200K, about 5× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both Claude Sonnet 4.5 and Qwen 3.6 Plus together?

Yes — a multi-model platform like LumiChats gives you Claude Sonnet 4.5, Qwen 3.6 Plus 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 4.5 or Qwen 3.6 Plus?

Qwen 3.6 Plus — released March 31, 2026, about 6 months after Claude Sonnet 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.