What is the difference between Qwen3.5 Plus 2026-02-15 and Seed 2.1 Turbo?

Qwen3.5 Plus 2026-02-15 is developed by Qwen while Seed 2.1 Turbo is developed by ByteDance. Qwen3.5 Plus 2026-02-15 has a 1.0M token context window vs Seed 2.1 Turbo's 262K. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, Qwen3.5 Plus 2026-02-15 or Seed 2.1 Turbo?

It depends on your use case. Qwen3.5 Plus 2026-02-15 and Seed 2.1 Turbo each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 53 challenges so you can judge which fits your needs best.

How much does Qwen3.5 Plus 2026-02-15 cost compared to Seed 2.1 Turbo?

Qwen3.5 Plus 2026-02-15 costs $0.4/M input tokens and Seed 2.1 Turbo costs $0.5/M input tokens. Qwen3.5 Plus 2026-02-15 is $0.10/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare Qwen3.5 Plus 2026-02-15 and Seed 2.1 Turbo on Rival?

This page shows a side-by-side comparison of Qwen3.5 Plus 2026-02-15 and Seed 2.1 Turbo across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

Updated Aug 2026

Qwen3.5 Plus 2026-02-15vsSeed 2.1 Turbo

Qwen3.5 Plus 2026-02-15 is cheaper than Seed 2.1 Turbo at $0.4/M vs $0.5/M input tokens.

Qwen3.5 Plus 2026-02-15 and Seed 2.1 Turbo compared across 53 shared prompts
Spec	Qwen3.5 Plus 2026-02-15	Seed 2.1 Turbo
Input price	$0.4/M tokens	$0.5/M tokens
Output price	$2.4/M tokens	$2.5/M tokens
Context window	1.0M tokens	262K tokens
Weights	Closed	—
Free API (OpenRouter)	No	No
Released	Feb 2026	Aug 2026