o1 vs GPT-3.5 Turbo

Compare o1 and GPT-3.5 Turbo, both from OpenAI, context windows of 128K vs 16K, tested across 24 shared challenges. Updated April 2026.

Which is better, o1 or GPT-3.5 Turbo?

o1 and GPT-3.5 Turbo are both competitive models. o1 costs $15/M input tokens vs $1.5/M for GPT-3.5 Turbo. Context windows: 128K vs 16K tokens. Compare their real outputs side by side below.

Key Differences Between o1 and GPT-3.5 Turbo

o1 is made by openai while GPT-3.5 Turbo is from openai. o1 has a 128K token context window compared to GPT-3.5 Turbo's 16K. On pricing, o1 costs $15/M input tokens vs $1.5/M for GPT-3.5 Turbo.

Our Verdict
o1
o1
GPT-3.5 Turbo
GPT-3.5 TurboRunner-up

No community votes yet. On paper, o1 has the edge — newer, bigger context window.

GPT-3.5 Turbo is 30x cheaper per token — worth considering if cost matters.

Too close to call
Writing DNA

Style Comparison

Similarity
88%

o1 uses 503.7x more bold

o1
GPT-3.5 Turbo
64%Vocabulary61%
16wSentence Length16w
0.76Hedging0.23
5.0Bold0.0
2.6Lists3.7
0.00Emoji0.00
0.44Headings0.00
0.40Transitions0.38
Based on 13 + 11 text responses
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o1GPT-3.5 Turbo
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