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GPT-5 Mini

Parameters

100B (Estimated)

Context Length

400K

Modality

Text

Architecture

Undisclosed

License

Proprietary

Release Date

13 Nov 2025

Knowledge Cutoff

May 2024

API Pricing (per 1M)

Input: $0.25 · Output: $2.00

Evaluation Benchmarks

Rank

#51

BenchmarkScoreRank

0.825

14

Software Engineering

SWE-bench Verified

0.60

28

Graduate-Level QA

GPQA

0.823

57

Web Development

WebDev Arena
medium

1419

61

General Text

Text Arena
high

1390

103

Agentic Index

Artificial Analysis
high

0.09

104

Intelligence Index

Artificial Analysis
high

0.17

medium

0.21

low

0.10

144

126

189

high

0.16

137

Summarization

Archived
ProLLM Summarization

0.982

🥇

1

Rankings

Overall Rank

#51

Coding Rank

#47

About GPT-5 Mini

GPT-5 Mini is a lightweight, cost-effective reasoning model from OpenAI optimized for high-volume conversational and agentic workloads. It provides native multimodal support and adjustable thinking effort within an expanded context window.

Technical Specifications

Architecture specifications are undisclosed for proprietary models.

Attention

Attention Structure

Multi-Head Attention

Attention Heads

Undisclosed

Key-Value Heads

Undisclosed

Attention Head Dimension

Undisclosed

Position Embedding

Absolute Position Embedding

RoPE Theta

Undisclosed

Sliding Window Attention

Undisclosed

Sliding Window Size

Undisclosed

Sliding Window Ratio

Undisclosed

Linear Attention

Undisclosed

Linear Attention Ratio

Undisclosed

Normalization

Undisclosed

Activation Function

Undisclosed

Dimensions

Hidden Dimension Size

Undisclosed

Number of Layers

Undisclosed

FFN Intermediate Size (Dense)

Undisclosed

Multi-Token Prediction Heads

Undisclosed

Tokenizer

Vocabulary Size

Undisclosed

About GPT-5

OpenAI's latest generation of language models featuring advanced reasoning capabilities, extended context windows up to 400K tokens, and specialized variants for coding, general intelligence, and efficiency. GPT-5 series introduces improved thinking modes, superior performance across benchmarks, and variants optimized for different use cases from high-capacity Pro models to efficient Nano models. Features native multimodal understanding, enhanced mathematical reasoning, and state-of-the-art coding abilities through Codex variants.


Other GPT-5 Models