GPT-5.5

Apr 2026
GPT-5.5
Compare in
on
$2.10per task?
$5 / $30per 1M in / outcache $0.50
92 tok/sfirst token in 80 s?
1.05Mcontext

Rankingat xhigh effort?

History

17 versions
50607080Jan 26Apr 26Release dateMCP-Atlas Public5.1 · Nov5.2 · Dec5.4 · Mar5.5
50607080Jan 26Apr 26Release dateMCP-Atlas Public5.1 · Nov5.2 · Dec5.4 · Mar5.5

Benchmarks

all categories
Chat & Knowledge
MLCR-AA28.9#9
HealthBench Professional length-adjustedlab51.8
HealthBench length-adjustedlab56.5
HealthBench Hard length-adjustedlab31.5
HealthBench Consensus length-adjustedlab95.6
Coding
SciCode55.8#26
SWE-bench Pro (edition unstated)lab58.6
DeepSWE (edition unstated)lab70
MultiLangBenchlab25.8
Meta Internal Coding Benchlab67.1
Agents & Tool Use
Toolathlon-Verified73.5#6
MCP-Atlas · full 100075.3#5
MCP-Atlas Public79.4#4
EBR Bench34.3#11
OSWorld-Verifiedlab78.7
MCP Atlaslab75.3
JobBenchlab38.3
Humanity’s Last Exam with toolslab52.2
Finance Agent v2lab51.8
DeepSearchQAlab87.8
Writing & Language
Vision & Documents
CharXiv Reasoninglab84.8
BabyVisionlab83.6

Watch out 1

Prompts with >272K input tokens›

Above 272K input tokens, input costs 2× and output 1.5× for the full session in Standard, Batch and Flex. Source ↗

FAQ

How much does GPT-5.5 cost?›

$5 per 1M input tokens and $30 per 1M output tokens; cached input $0.50 per 1M. A typical benchmark task costs about $2.10 at xhigh effort.

Is GPT-5.5 free to use?›

There is no free API; the cheapest paid price is $5 per 1M input tokens.

How good is GPT-5.5, and what is it best at?›

#23 of 336 in Chat & Knowledge, #33 of 134 in Coding, #41 of 135 in Agents & Tool Use, #20 of 197 in Writing & Language, #21 of 125 in Vision & Documents. Strongest at: Coding, Tool calling, Reasoning, Science, Long context, Knowledge, Instructions, Vision.

Is GPT-5.5 better than GPT-5.4?›

On MCP-Atlas Public, GPT-5.5 scores 79.4 vs 75.4 — higher.

How can I use GPT-5.5?›

Through the API of Amazon Bedrock, Azure, OpenAI.

What is the context window of GPT-5.5?›

1.05M tokens, with up to 128K output tokens.

When was GPT-5.5 released? Is there a newer version?›

Released 2026-04-23. It has been superseded by GPT-5.6 Sol.

Is GPT-5.5 open source?›

No, GPT-5.5 is a closed model available through an API.

Can GPT-5.5 read images?›

It accepts text and images, PDF files as input.

What is GPT-5.5?›

GPT-5.5 is a closed language model from OpenAI, released Apr 2026, the successor to GPT-5.4.

What are the best alternatives to GPT-5.5?›

Muse Spark (cheaper).