Claude Sonnet 5.5 vs Qwen3.8 Flash Next: Specs & Benchmark Comparison

Claude Sonnet 5.5 is developed by Anthropic, while Qwen3.8 Flash Next comes from Alibaba. Qwen3.8 Flash Next was released in August 2026, and Claude Sonnet 5.5 followed a month later in September 2026. Qwen3.8 Flash Next has a published size of about 180 billion parameters; Anthropic has not disclosed the parameter count of Claude Sonnet 5.5.

The two models share 3 published benchmarks. Claude Sonnet 5.5 leads on 3 of them. The widest gaps are on SWE-Bench Pro, where Claude Sonnet 5.5 scores 81.3% against 62.5%; DeepSWE 1.1, where Claude Sonnet 5.5 scores 71.0% against 58.7%. Averaged across everything we track, Claude Sonnet 5.5 sits at 67.4% and Qwen3.8 Flash Next at 67.1%.

Qwen3.8 Flash Next is the cheaper API at $0.16 per million input tokens and $0.47 per million output tokens, roughly 13 times cheaper than Claude Sonnet 5.5 at $2 and $10. Both accept a context window of about 1M tokens. Claude Sonnet 5.5 accepts text and images as input, while Qwen3.8 Flash Next accepts text, images, and video.

CharacteristicClaude Sonnet 5.5Qwen3.8 Flash Next
CompanyAnthropicAlibaba
Release DateSeptember 28, 2026August 26, 2026
Parameters—180B
MultimodalYesYes
Context (input)1.0M1.0M
Context (output)128K66K
Input Price / 1M$2.00$0.16
Output Price / 1M$10.00$0.47
Average Score67.4%67.1%
Benchmarks
SWE-Bench Pro81.3%62.5%
DeepSWE 1.171.0%58.7%
SWE-bench Multilingual90.3%81.0%

Visual Benchmark Comparison

Claude Sonnet 5.5
Qwen3.8 Flash Next
SWE-Bench Pro0.8 vs 0.6
0.8
0.6
DeepSWE 1.10.7 vs 0.6
0.7
0.6
SWE-bench Multilingual0.9 vs 0.8
0.9
0.8

Verdict

Both models show equal results — the choice depends on your specific use case.

Overall Performance

Both models show comparable average scores: Claude Sonnet 5.5 — 0.7, Qwen3.8 Flash Next — 0.7.

API Cost

Qwen3.8 Flash Next is 19.0x cheaper: input $0.16/1M vs $2.00/1M tokens.

Context Window

Same context size: 1M tokens.

Recency

Claude Sonnet 5.5 is newer: released 9/28/2026 vs 8/26/2026.

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Frequently Asked Questions

Which is better for coding — Claude Sonnet 5.5 or Qwen3.8 Flash Next?
Direct comparison on the SWE-Bench benchmark is not available. We recommend reviewing other metrics on the comparison page.
Which model is cheaper — Claude Sonnet 5.5 or Qwen3.8 Flash Next?
Qwen3.8 Flash Next is cheaper for input: $0.16 per 1M tokens vs $2.00.
Which has a larger context window — Claude Sonnet 5.5 or Qwen3.8 Flash Next?
Claude Sonnet 5.5 supports a larger context: 1,048,576 tokens vs 1,048,576.

The Claude Sonnet 5.5 and Qwen3.8 Flash Next comparison is updated for 2026. Data includes benchmark results, API pricing, context window size and other specifications. For more detailed information, visit the Claude Sonnet 5.5 or Qwen3.8 Flash Next page. See also the complete list of AI model comparisons.