Model Comparison

GPT-5.5 (high)
vs. GPT-5 (medium)

Comparing 2 AI models · 12 benchmarks · OpenAI

Recommended Pick

OpenAI logo GPT-5.5 (high) 11 metric wins

Strongest on: TTFT, Latency, Intelligence

Best Value

OpenAI logo

GPT-5 (medium)

100.0 value score

73.7 reasoning / $3.44/1M

Lowest Price

OpenAI logo

GPT-5 (medium)

$1.25/1M input price

Best Reasoning

OpenAI logo

GPT-5 (medium)

73.7 reasoning score

Blends available reasoning benchmarks

Best for Coding

OpenAI logo

GPT-5.5 (high)

58.5 coding index

Composite Indices

Higher is better; speed and price are normalized

Standard Benchmarks

Only benchmarks with data are shown

Differences That Matter

Best value

GPT-5 (medium) has the strongest quality-to-price mix at 100.0 out of 100 value points.

Price gap

GPT-5 (medium) is 4.0x cheaper on input tokens than GPT-5.5 (high).

Speed gap

GPT-5 (medium) generates about 1.5x as many tokens per second as GPT-5.5 (high).

Reasoning gap

GPT-5 (medium) leads GPT-5.5 (high) by 10.6 points on reasoning.

Coding gap

GPT-5.5 (high) leads GPT-5 (medium) by 19.6 points on coding.

Live compare

Response Face-Off

Run one prompt through the selected models and compare response quality with live speed and cost context.

OpenAI logo

GPT-5.5 (high)

OpenAI

Waiting

TTFT

Time

tok/s

Tokens

Cost

Waiting
OpenAI logo

GPT-5 (medium)

OpenAI

Waiting

TTFT

Time

tok/s

Tokens

Cost

Waiting

Which answer was more useful?

AI Chat

Chat with 80+ models

Inference API

EU-hosted inference

Full Comparison

Metric
Top Pick
OpenAI logo GPT-5.5 (high)
OpenAI
OpenAI logo GPT-5 (medium)
OpenAI
Pricing per 1M tokens
Input Cost $5.00/1M$1.25/1M
Output Cost $30.00/1M$10.00/1M
Blended (3:1) $11.25/1M$3.44/1M
Specifications
Organization OpenAIOpenAI
Release Date Apr 23, 2026Aug 7, 2025
Performance & Speed
Throughput 58.9 tok/s86.2 tok/s
TTFT 20702ms41696ms
Latency 20702ms41696ms
Composite Indices
Value Score 26.2100.0
Reasoning Score 63.173.7
Intelligence 53.133.7
Coding 58.538.9
Math 91.7
Standard Benchmarks
GPQA 93.2%84.2%
MMLU Pro 86.7%
HLE 43.0%23.5%
LiveCodeBench 70.3%
MATH 500 99.1%
AIME 2025 91.7%
AIME (Original) 91.7%
SciCode 55.9%41.1%
LCR 73.3%72.8%
IFBench 71.6%70.6%
TAU-bench v2 93.0%86.5%
TerminalBench Hard 59.8%37.9%

Key Takeaways

GPT-5 (medium) offers the best value at $1.25/1M, making it ideal for high-volume applications and cost-conscious projects.

GPT-5 (medium) has the strongest reasoning profile with a 73.7 reasoning score, combining the available reasoning-heavy benchmarks.

GPT-5.5 (high) reaches a 58.5 coding index, making it the top choice for software development and code generation tasks.

All models support context windows of ∞+ tokens, suitable for processing lengthy documents and maintaining extended conversations.

When to Choose Each Model

OpenAI logo

GPT-5.5 (high)

  • Code generation
  • Software development
OpenAI logo

GPT-5 (medium)

  • Cost-sensitive applications
  • High-volume processing
  • Complex reasoning tasks
  • Research & analysis