Which is cheaper, Claude Sonnet 5.5 and Qwen3.8 27B?

Qwen3.8 27B has the lowest input price. Per 1M input tokens: Claude Sonnet 5.5 from $2.00 and Qwen3.8 27B from $0.40.

Which has the larger context window, Claude Sonnet 5.5 and Qwen3.8 27B?

Claude Sonnet 5.5 has the largest context window: Claude Sonnet 5.5 1,000,000 tokens and Qwen3.8 27B 262,144 tokens.

Which is smarter, Claude Sonnet 5.5 and Qwen3.8 27B?

Claude Sonnet 5.5 scores highest on the Artificial Analysis Intelligence Index: Claude Sonnet 5.5 54.2 and Qwen3.8 27B 20.1.

Can I switch between Claude Sonnet 5.5 and Qwen3.8 27B without changing my code?

Yes. All of them are served through FastRouter's OpenAI-compatible API, so switching is a change of the model parameter (anthropic/claude-sonnet-5.5, qwen/qwen3.8-27b).

Claude Sonnet 5.5 vs Qwen3.8 27B

Side-by-side pricing per provider, context window, benchmark scores and speed, all on one OpenAI-compatible API.

Estimate monthly cost for these models

Claude Sonnet 5.5 Anthropicanthropic/claude-sonnet-5.5

Qwen3.8 27B Alibabaqwen/qwen3.8-27b

Creator

Anthropic

Alibaba

Released

Sep 28, 2026

Aug 14, 2025

Context window

262K

Max output

128K

33K

Input / 1MLowest provider price

$2.00

$0.40

Output / 1MLowest provider price

$10.00

$3.00

Providers

IntelligenceArtificial Analysis index

54.2

20.1

Accepts

Text, Image

Text, Image, Video

Produces

Text

Tool calling

Yes

Structured output

Yes

Reasoning

Yes

Claude Sonnet 5.5 vs Qwen3.8 27B: summary

Claude Sonnet 5.5 and Qwen3.8 27B are both available through FastRouter's OpenAI-compatible API, so switching between them is a change of model id, not a new integration.

Claude Sonnet 5.5, from Anthropic, has a 1,000,000-token context window, costs from $2.00/1M input and $10.00/1M output tokens across 3 providers and scores 54.2 on the Artificial Analysis Intelligence Index.

Qwen3.8 27B, from Alibaba, has a 262,144-token context window, costs $0.40/1M input and $3.00/1M output tokens and scores 20.1 on the Artificial Analysis Intelligence Index.

Qwen3.8 27B is the cheapest on input, 5× cheaper than the next model, Claude Sonnet 5.5 has the largest context window and Claude Sonnet 5.5 scores highest for intelligence.

Switch with one line

client = OpenAI(base_url="https://api.fastrouter.ai/api/v1", api_key="<FASTROUTER_API_KEY>") client.chat.completions.create(model="anthropic/claude-sonnet-5.5", messages=[...]) # or client.chat.completions.create(model="qwen/qwen3.8-27b", messages=[...])

Full API docs

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More comparisons

Benchmark scores sourced from ArtificialAnalysis