GPT 5.3 Codex

Release Date: Feb 24, 2026     Creator: OpenAI

OpenAI's model optimized for coding tasks

Access GPT 5.3 Codex securely with complete privacy. Our local-first approach means your text chats and prompts are stored exclusively on your browser via IndexedDB, never on a remote server. When you delete a chat, it is permanently wiped locally, and we ensure zero prompt training is used across all model endpoints.

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Model Specifications
Knowledge Cutoff
Aug 31, 2025
N/A
Context (VividLLM)
128,000 Tokens
N/A
With a context window of 128,000 tokens, this model can 'remember' and analyze up to 192 pages of data at once. This makes it a top choice for debugging entire codebases and summarizing full-length books.
Context (Native)
400,000 Tokens
N/A
Input ModalitiesTextImagePDFTextImagePDF
Tool Calling
yes
N/A
Output TypeTextText
Default Max Output81928192
Input Weight
1.000 x (Pro)
N/A
Output Weight
2.200 x (Pro)
N/A

Disclaimer: We are providing Image Upload options to only limit models as of now, so some models which have image upload options might now have that feature on our site.

GPT 5.3 Codex: Secure & Private Access | No Prompt training