GPT-5.3 Instant
speedOpenAI•Released on 2026-03-05
GPT-5.3 Instant is OpenAI's speed-optimized model designed for applications where latency matters as much as quality. It features a 26.8% reduction in hallucinations compared to GPT-5.2, an 'anti-cringe' tone overhaul that eliminates performative language patterns, and sub-800ms time-to-first-token latency. Available through the OpenAI API as gpt-5.3-chat and in ChatGPT Plus, Team, and Enterprise.
84
Overall Score
Core Specs
128K
Context Window
16K
Max Output
ReasoningOpen Sourcetextimage
Scenario Scores
Pros & Cons
Sentiment0% +0% ·0% −
Pros
- +Sub-800ms time-to-first-token latency
- +26.8% fewer hallucinations than GPT-5.2
- +Anti-cringe tone: natural, direct responses
- +Full function calling & structured outputs
- +Affordable speed-tier pricing
Cons
- −128K context (smaller than GPT-5.4's 1M)
- −No reasoning mode
- −No computer use capability
- −16K max output tokens
Pricing
Input (per 1M tokens)$1.75
Output (per 1M tokens)$14.00
Subscription$20/month
Free trial available
Updated on 2026-03-12
Get Started
1Visit the provider's website
2Create an account
3Start using the model
Benchmarks
simpleQA93.9%
sweVerified64.7%
math50092.3%
mmluPro84.1%
mmmu73.8%
humanEval95.1%
gpqaDiamond61.4%