What is the difference between GPT-4o (Omni) and GPT-4.5?

Both are developed by OpenAI but target different use cases. GPT-4o (Omni) has a 128K token context window vs GPT-4.5's 128K. in 7 community votes on Rival, GPT-4o (Omni) wins 57% of head-to-head matchups. These results are based on blind head-to-head voting across 25 challenges.

Which is better, GPT-4o (Omni) or GPT-4.5?

Based on 7 community votes on Rival, GPT-4o (Omni) wins 57% of head-to-head matchups against GPT-4.5. GPT-4o (Omni) is strongest in Reasoning.

How much does GPT-4o (Omni) cost compared to GPT-4.5?

GPT-4o (Omni) costs $2.5/M input tokens and GPT-4.5 costs $75/M input tokens. GPT-4o (Omni) is $72.50/M cheaper per input. GPT-4o (Omni) also wins more often in community votes, making it the better value.

How are GPT-4o (Omni) vs GPT-4.5 votes collected on Rival?

Rival presents both models' outputs side-by-side in blind duels. Voters see the responses but don't know which model produced each one, eliminating brand bias. 7 votes have been collected for this pair across 25 challenges. All vote data is part of Rival's open dataset.

Rival

Updated Feb 27, 2025

GPT-4o (Omni)vsGPT-4.5

25 fights queued

Why GPT-4o (Omni)?

17.1x cheaper overall$2.50/M in · $10.00/M out

Why GPT-4.5?

Leads 3 of 3 benchmarks

Stronger on GPQA69.5% vs 53.1%

10 months newerFeb 2025

GPT-4o (Omni)GPT-4.5

Input price

$2.50/M

$75.00/M

Output price

$10.00/M

$150.00/M

Context

128K

Released

May 2024

Feb 2025

Benchmarks3 common

MMLU

88.7%

90.8%+2.3%

GPQA

53.1%

69.5%+23.6%

MATH

75.9%

87.1%+12.9%

Favorites

GPT-4o (Omni)GPT-4.5

Movie

Inception

20108.4

—

Album

Dark Side Of The Moon

suisside

—

Book

To Kill a Mockingbird

Harper Lee

—

City

Kyoto

Japan

—

Game

The Legend of Zelda: Breath of the Wild

Adventure, Action4.5

—

6 / 25

Estimate Complexityreasoning

Tests an AI's ability to make educated estimates based on technical knowledge

GPT-4o (Omni)

Openai · May 2024text

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

GPT-4.5

Openai · Feb 2025text

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Vote

2 / 25

AI Board Game Logicreasoning

Tests an AI's ability to understand game rules and strategy

GPT-4o (Omni)

Openai · May 2024svg

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

GPT-4.5

Openai · Feb 2025svg

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Vote

3 / 25

Logic Puzzlereasoning

Tests an AI's ability to solve a simple but potentially confusing logic puzzle

GPT-4o (Omni)

Openai · May 2024text

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

GPT-4.5

Openai · Feb 2025text

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Vote

4 / 25

Math Misconception Testreasoning

Tests an AI's understanding of number representation

GPT-4o (Omni)

Openai · May 2024text

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

GPT-4.5

Openai · Feb 2025text

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Vote

5 / 25

SVG Layout Challengeimage generation

Tests an AI's ability to generate vector graphics

GPT-4o (Omni)

Openai · May 2024svg

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

GPT-4.5

Openai · Feb 2025svg

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Vote

6 / 25

Xbox Controller SVG Artimage generation

Tests an AI's ability to create detailed SVG illustrations of gaming hardware

GPT-4o (Omni)

Openai · May 2024svg

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

GPT-4.5

Openai · Feb 2025svg

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Vote

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Our Verdict

GPT-4o (Omni)Winner

GPT-4.5Runner-up

GPT-4o (Omni) has the edge overall. In 7 blind votes, GPT-4o (Omni) wins 57% of the time.

GPT-4o (Omni) particularly excels in Reasoning. GPT-4o (Omni) is 15x cheaper per token — worth considering if cost matters.

Slight edge

These are our prompts. Yours will tell you more.

Run GPT-4o (Omni) vs GPT-4.5 on your actual task. 5 free credits. No card.

Test with your prompt

FAQ

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GPT-4o (Omni) vs GPT-4.5

Which is better, GPT-4o (Omni) or GPT-4.5?