What is the difference between GPT-4.5 and GPT-5 Pro?

Both are developed by OpenAI but target different use cases. GPT-4.5 has a 128K token context window vs GPT-5 Pro's 400K. You can compare their actual outputs across 17 challenges on Rival to see how they differ in practice.

Which is better, GPT-4.5 or GPT-5 Pro?

It depends on your use case. GPT-4.5 and GPT-5 Pro each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 17 challenges so you can judge which fits your needs best.

How much does GPT-4.5 cost compared to GPT-5 Pro?

GPT-4.5 costs $75/M input tokens and GPT-5 Pro costs $15/M input tokens. GPT-5 Pro is $60.00/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 GPT-4.5 and GPT-5 Pro on Rival?

This page shows a side-by-side comparison of GPT-4.5 and GPT-5 Pro 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 GPT-4.5 and GPT-5 Pro?

Both are developed by OpenAI but target different use cases. GPT-4.5 has a 128K token context window vs GPT-5 Pro's 400K. You can compare their actual outputs across 17 challenges on Rival to see how they differ in practice.

Which is better, GPT-4.5 or GPT-5 Pro?

It depends on your use case. GPT-4.5 and GPT-5 Pro each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 17 challenges so you can judge which fits your needs best.

How much does GPT-4.5 cost compared to GPT-5 Pro?

GPT-4.5 costs $75/M input tokens and GPT-5 Pro costs $15/M input tokens. GPT-5 Pro is $60.00/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 GPT-4.5 and GPT-5 Pro on Rival?

This page shows a side-by-side comparison of GPT-4.5 and GPT-5 Pro 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.

GPT-4.5 vs GPT-5 Pro: Which Is Better?

Updated Oct 2025

Our Verdict

GPT-5 Pro

GPT-4.5Runner-up

No community votes yet. On paper, GPT-5 Pro has the edge — newer, bigger context window.

Too close to call

API pricing

Cost per 1M tokens

GPT-4.5

Input

$75.00

Output

$150.00

GPT-5 Pro

Input

$15.00

5.0× cheaper

Output

$120.00

1.3× cheaper

GPT-5 Pro is cheaper on both — 5.0× input, 1.3× output

Writing DNA

Style Comparison

Similarity

44%

GPT-4.5 uses 466.6x more bold

GPT-4.5

GPT-5 Pro

63%Vocabulary65%

16wSentence Length15w

0.57Hedging0.32

4.7Bold0.0

6.4Lists2.9

0.00Emoji0.00

1.30Headings0.00

0.54Transitions0.01

Based on 11 + 11 text responses

Research

What we learned reading every model

GPT-4.5 and GPT-5 Pro 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

GPT-5 Pro vs Llama 4 MaverickNew provider

GPT-5 Pro vs GPT-5Version compare

GPT-4.5 vs MiniMax M3New provider

Updated Oct 2025

Our Verdict

GPT-5 Pro

GPT-4.5Runner-up

No community votes yet. On paper, GPT-5 Pro has the edge — newer, bigger context window.

Too close to call

API pricing

Cost per 1M tokens

GPT-4.5

Input

$75.00

Output

$150.00

GPT-5 Pro

Input

$15.00

5.0× cheaper

Output

$120.00

1.3× cheaper

GPT-5 Pro is cheaper on both — 5.0× input, 1.3× output

Writing DNA

Style Comparison

Similarity

44%

GPT-4.5 uses 466.6x more bold

GPT-4.5

GPT-5 Pro

63%Vocabulary65%

16wSentence Length15w

0.57Hedging0.32

4.7Bold0.0

6.4Lists2.9

0.00Emoji0.00

1.30Headings0.00

0.54Transitions0.01

Based on 11 + 11 text responses

Research

What we learned reading every model

GPT-4.5 and GPT-5 Pro 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

GPT-5 Pro vs Llama 4 MaverickNew provider

GPT-5 Pro vs GPT-5Version compare

GPT-4.5 vs MiniMax M3New provider