GPT-5.1vsSeed 2.1 Turbo
Seed 2.1 Turbo is cheaper than GPT-5.1 at $0.5/M vs $1.25/M input tokens.
| Spec | GPT-5.1 | Seed 2.1 Turbo |
|---|---|---|
| Input price | $1.25/M tokens | $0.5/M tokens |
| Output price | $10/M tokens | $2.5/M tokens |
| Context window | 400K tokens | 262K tokens |
| Weights | Closed | — |
| Free API (OpenRouter) | No | No |
| Released | Nov 2025 | Aug 2026 |
Our Verdict
GPT-5.1
Seed 2.1 TurboRunner-up
Not enough votes to call it. On the specs, GPT-5.1 has the edge: bigger model tier, bigger context window, major provider backing.
Seed 2.1 Turbo costs 4.0x less per token.
Too close to call
Reviewing agent-written code?See a Brief PR report
API pricing
Cost per 1M tokens
GPT-5.1
Input
$1.25
Output
$10.00
Seed 2.1 Turbo
Input
$0.50
2.5× cheaper
Output
$2.50
4.0× cheaper
Seed 2.1 Turbo is cheaper on both: 2.5× input, 4.0× output.
Where to run it
3 hosts
Seed 2.1 Turbo1 host
Per million tokens. Prices and uptime via OpenRouter, checked 13 Sep 2026.
Writing DNA
Style Comparison
Similarity
43%
Seed 2.1 Turbo uses 6.6x more emoji
GPT-5.1
Seed 2.1 Turbo
62%Vocabulary50%
19wSentence Length27w
0.29Hedging0.27
3.5Bold1.5
7.2Lists2.4
0.00Emoji0.07
0.61Headings1.01
0.03Transitions0.04
Based on 14 + 27 text responses
Research
What we learned reading every model
FAQ
Common questions
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