GPT-5.3 Chat Latest
JSON →The latest chat-optimized variant of GPT-5.3, offering improved conversational abilities over GPT-5.2.
Specs
context window 128K tokens
max output 16K tokens
input price $1.75 / 1M tokens
output price $14 / 1M tokens
Capabilities
tool-usejson-modestreamingreasoningcode-generationfunction-callingvisionprompt-caching
Dates
releasedMar 2026
knowledge cutoffDec 2025
Resources
API
full doc /v1/models/gpt-5.3-chat-latest