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Head-to-head comparison

Claude Opus 5 vs Qwen3.8 Flash

Claude Opus 5 (Anthropic) and Qwen3.8 Flash (Qwen) compared on the ModelCap Index, API price, context window, provider availability, weight access and every public benchmark board they share. Figures are the same ones shown on the live rankings; nothing here is a hidden score.

Snapshot as of 3 September 2026

As of 3 September 2026, Claude Opus 5 holds the stronger ModelCap Index position (#3 vs #17); and Qwen3.8 Flash is 53.2× cheaper per output token ($0.47/1M vs $25.00/1M).

Which should you choose?

Choose Claude Opus 5 if…

  • you want the stronger overall ModelCap Index position — #3 against #17 (83.6 vs 72.1 points).
  • you want provider choice — 5 listed API providers against 1.
  • AA Intelligence Index is your yardstick — 63.1 against 55.8.
  • AA Terminal-Bench 2.1 is your yardstick — 89.1% against 86.1%.
  • AA Humanity's Last Exam is your yardstick — 54.9% against 38.0%.

Choose Qwen3.8 Flash if…

  • API cost matters — $0.47/1M output tokens against $25.00/1M, about 53.2× cheaper.
  • your workload is prompt-heavy — input tokens cost $0.15/1M against $5.00/1M.
  • you want the more recently listed model — Qwen3.8 Flash was listed 26 August 2026, Claude Opus 5 24 July 2026.

Claude Opus 5 vs Qwen3.8 Flash: specs, pricing and context

Specification comparison of Claude Opus 5 and Qwen3.8 Flash
FieldClaude Opus 5AnthropicQwen3.8 FlashQwen
ModelCap Index position#3#17
Index score83.672.1
EvidenceMeasuredMeasured
Input price / 1M tokens$5.00$0.15
Output price / 1M tokens$25.00$0.47
Context window1M tokens1M tokens
Max output tokens128K131K
API providers listed51
Weight accessAPI onlyRestricted license
Input modalitiesText, Image, FileText, Image, Video
First listed24 July 202626 August 2026
PublisherAnthropicQwen

Evidence: 6 public benchmark observations across 6 boards · 1 public benchmark observation across 1 board. Prices are the lowest listed API offer per million tokens observed on the OpenRouter catalogue.

Benchmark scores: Claude Opus 5 vs Qwen3.8 Flash

Public benchmark boards where Claude Opus 5 or Qwen3.8 Flash has a published result
BoardClaude Opus 5Qwen3.8 FlashLeads
Arena codingArena (LMArena)15331526–1541High—Only one result
LMArena AgentLMArena13.8%12.0%–15.6%High—Only one result
ARC-AGI-2ARC Prize Foundation90.4%Max—Only one result
ARC-AGI-3ARC Prize Foundation30.2%High—Only one result
AA Intelligence IndexArtificial Analysis63.1intelligence-index55.8intelligence-indexClaude Opus 5
AA Terminal-Bench 2.1Artificial Analysis89.1%terminal-bench-2.186.1%terminal-bench-2.1Claude Opus 5
AA Humanity's Last ExamArtificial Analysis54.9%humanitys-last-exam38.0%humanitys-last-examClaude Opus 5
Terminal-Bench 4.0Terminal-Bench (Laude Institute)51.8%48.4%–55.2%Claude Code · Max—Only one result

Scores are the sources' own published figures for each model's best evaluated configuration; ModelCap never re-runs a benchmark.

Want a different pairing? Open the interactive comparison tool to swap either model for any current ranked language model.

Claude Opus 5 vs Qwen3.8 Flash: common questions

Is Claude Opus 5 better than Qwen3.8 Flash?

Claude Opus 5 ranks higher on the ModelCap Index as of 3 September 2026: #3 against #17. That is a capability ranking built from public benchmark evidence with published uncertainty; whether it is "better" for you also depends on price, context and where you can run it.

Is Claude Opus 5 cheaper than Qwen3.8 Flash?

Qwen3.8 Flash is cheaper on output tokens: $0.47/1M against $25.00/1M. Input tokens are $5.00/1M for Claude Opus 5 and $0.15/1M for Qwen3.8 Flash. Prices are the lowest listed API offer ModelCap observed, in USD per million tokens.

Which has the bigger context window, Claude Opus 5 or Qwen3.8 Flash?

Both publish a 1M-token context window.

Which is better for coding, Claude Opus 5 or Qwen3.8 Flash?

AA Terminal-Bench 2.1: Claude Opus 5 89.1%, Qwen3.8 Flash 86.1% — Claude Opus 5 leads.

Are Claude Opus 5 and Qwen3.8 Flash open-weight models?

Claude Opus 5: API only. Qwen3.8 Flash: Restricted license. Open weights mean the checkpoint can be downloaded and self-hosted under its licence; API-only models are available solely through hosted endpoints.

Where can I run Claude Opus 5 and Qwen3.8 Flash?

ModelCap currently lists 5 API providers for Claude Opus 5 and 1 for Qwen3.8 Flash, from the OpenRouter catalogue snapshot the site serves; each model page lists the providers and their prices.

How current is this Claude Opus 5 vs Qwen3.8 Flash comparison?

Every figure comes from the sealed ModelCap dataset published 3 September 2026; the page re-renders within a minute of each data refresh, and the ModelCap Index positions are the same ones shown on the live rankings.

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