by OpenAI

GPT-5.

text closed 256K ctx Transformer (MoE) Quality 86.0 Elo 1399
Cheapest input
$1.25/M
on OpenRouter
Cheapest output
$10.0/M
on OpenRouter
Fastest
30 tok/s
on OpenRouter
Hosted equiv.
~$3.6/hr
@ 100 tok/s on OpenRouter
Capability snapshot

What it's best at.

Math 96.0
Coding 93.2
General knowledge 91.0
Reasoning 87.5

Scores normalised against benchmark ceilings (100 = perfect). Coloured by tier — coral 80+ frontier, lavender 65+ strong, sage 50+ solid, slate below.

Benchmarks

Published scores.

Benchmark Score Source
GPQA 71.0 official ↗
MATH 96.0 official ↗
MMLU 91.0 official ↗
MMMU 78.0 official ↗
MMLU-Pro 87.5 official ↗
HumanEval 93.2 official ↗
SWE-bench 74.9 official ↗
Leaderboard standing

Independent rankings.

LMSYS Chatbot Arena
1399
Rank #1 · Elo from blind head-to-head votes
View leaderboard ↗
Artificial Analysis Quality Index
87.5
Composite of reasoning + coding + tool-use benchmarks
View on Artificial Analysis ↗
Description

About GPT-5.

GPT-5 is OpenAI's flagship model, released August 2025 as a unified replacement for the o3/4o/o3-mini split. It introduces dynamic routing between fast and deliberative modes — the API picks the right one per prompt, with optional reasoning_effort overrides. Supports 256K context, vision inputs, function calling, structured outputs, and built-in code interpreter. Leads MMLU-Pro and GPQA benchmarks; trades the SWE-bench top spot with Claude Sonnet 4.6. Available via OpenAI's API, ChatGPT, Azure OpenAI Service, and (mirrored) on aggregators like OpenRouter.

Architecture

How it's built.

Architecture
Transformer (MoE)
Knowledge cutoff
Apr 2025
99 days from cutoff to release.
Context window

How much it can remember.

256K tokens ≈ 192,000 English words
4K 32K 128K 1M
Max output per call: 16K tokens
Capabilities

What it can do.

Vision input
Audio input
· Video input
Function calling
Tool use
JSON mode
Streaming
Fine-tuning