What is the difference between Claude 3 Opus and GPT-5.3 Chat?

Claude 3 Opus is developed by Anthropic while GPT-5.3 Chat is developed by OpenAI. Claude 3 Opus has a 200K token context window vs GPT-5.3 Chat's 128K. You can compare their actual outputs across 12 challenges on Rival to see how they differ in practice.

Which is better, Claude 3 Opus or GPT-5.3 Chat?

It depends on your use case. Claude 3 Opus and GPT-5.3 Chat each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 12 challenges so you can judge which fits your needs best.

How much does Claude 3 Opus cost compared to GPT-5.3 Chat?

Claude 3 Opus costs $15/M input tokens and GPT-5.3 Chat costs $1.75/M input tokens. GPT-5.3 Chat is $13.25/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 Claude 3 Opus and GPT-5.3 Chat on Rival?

This page shows a side-by-side comparison of Claude 3 Opus and GPT-5.3 Chat 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.

What is the difference between Claude 3 Opus and GPT-5.3 Chat?

Claude 3 Opus is developed by Anthropic while GPT-5.3 Chat is developed by OpenAI. Claude 3 Opus has a 200K token context window vs GPT-5.3 Chat's 128K. You can compare their actual outputs across 12 challenges on Rival to see how they differ in practice.

Which is better, Claude 3 Opus or GPT-5.3 Chat?

It depends on your use case. Claude 3 Opus and GPT-5.3 Chat each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 12 challenges so you can judge which fits your needs best.

How much does Claude 3 Opus cost compared to GPT-5.3 Chat?

Claude 3 Opus costs $15/M input tokens and GPT-5.3 Chat costs $1.75/M input tokens. GPT-5.3 Chat is $13.25/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 Claude 3 Opus and GPT-5.3 Chat on Rival?

This page shows a side-by-side comparison of Claude 3 Opus and GPT-5.3 Chat 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.

Claude 3 Opus vs GPT-5.3 Chat: Which Is Better?

Updated Mar 2026

Our Verdict

Claude 3 Opus

GPT-5.3 ChatRunner-up

No community votes yet. On paper, Claude 3 Opus has the edge — bigger model tier, bigger context window.

GPT-5.3 Chat is 5.4x cheaper per token — worth considering if cost matters.

Too close to call

API pricing

Cost per 1M tokens

Claude 3 Opus

Input

$15.00

Output

$75.00

GPT-5.3 Chat

Input

$1.75

8.6× cheaper

Output

$14.00

5.4× cheaper

GPT-5.3 Chat is cheaper on both — 8.6× input, 5.4× output

Writing DNA

Style Comparison

Similarity

47%

GPT-5.3 Chat uses 171.1x more bold

Claude 3 Opus

GPT-5.3 Chat

54%Vocabulary59%

14wSentence Length26w

0.48Hedging0.84

0.0Bold1.7

3.0Lists6.6

0.00Emoji0.00

0.00Headings0.00

0.06Transitions0.25

Based on 3 + 23 text responses

Research

What we learned reading every model

Claude 3 Opus and GPT-5.3 Chat have opinions about your brand too.Ask 10 models what they tell people about you. Verbatim receipts.Run the mirror

FAQ

Common questions

Keep exploring

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Claude 3 Opus vs Llama 4 MaverickNew provider

Claude 3 Opus vs Grok 3New provider

Updated Mar 2026

Our Verdict

Claude 3 Opus

GPT-5.3 ChatRunner-up

No community votes yet. On paper, Claude 3 Opus has the edge — bigger model tier, bigger context window.

GPT-5.3 Chat is 5.4x cheaper per token — worth considering if cost matters.

Too close to call

API pricing

Cost per 1M tokens

Claude 3 Opus

Input

$15.00

Output

$75.00

GPT-5.3 Chat

Input

$1.75

8.6× cheaper

Output

$14.00

5.4× cheaper

GPT-5.3 Chat is cheaper on both — 8.6× input, 5.4× output

Writing DNA

Style Comparison

Similarity

47%

GPT-5.3 Chat uses 171.1x more bold

Claude 3 Opus

GPT-5.3 Chat

54%Vocabulary59%

14wSentence Length26w

0.48Hedging0.84

0.0Bold1.7

3.0Lists6.6

0.00Emoji0.00

0.00Headings0.00

0.06Transitions0.25

Based on 3 + 23 text responses

Research

What we learned reading every model

Claude 3 Opus and GPT-5.3 Chat have opinions about your brand too.Ask 10 models what they tell people about you. Verbatim receipts.Run the mirror

FAQ

Common questions

Keep exploring

More comparisons

Claude 3 Opus vs MiniMax M3New provider

Claude 3 Opus vs Llama 4 MaverickNew provider

Claude 3 Opus vs Grok 3New provider