Context Window

Compare

Gpt 4o Realtime Preview 2025 06 03 vs GPT Chat Latest

This page is context-first: how much text each model can take in one request. Full specs adds capabilities and limits; the pricing matrix below is only about $/million tokens from hosts that list both models.

Openai

Model

Gpt 4o Realtime Preview 2025 06 03

Tool calling

Context window

128K

128,000 tokens · ~96K words

Model page
Openai

Model

GPT Chat Latest

Image inputTool calling

Context window

400K

400,000 tokens · ~300K words

Model page

Context window · side by side

Bar length is relative to the larger of the two windows (100% = max of this pair). This is not pricing.

Gpt 4o Realtime Preview 2025 06 03128K
GPT Chat Latest400K

GPT Chat Latest has about 3.1× the context window of the other in this pair.

Token calculator →Memory savings →

GPT Chat Latest has 212% more context capacity (400K vs 128K tokens).

Quick verdicts

Short takeaways — validate with your own workloads.

  • Long document processing

    Use GPT Chat Latest. Its 400K context fits entire documents without chunking (vs 128K).

  • Long output (reports, code files)

    Use GPT Chat Latest. Its 128K max output lets you generate complete artifacts in one request.

Full specs

Context, output, capabilities, and dates. Green highlights the favorable value where we compute a winner.

SpecGpt 4o Realtime Preview 2025 06 03GPT Chat Latest
Context window128,000 tokens (128K)400,000 tokens (400K)
Max output tokens4,096 tokens (4K)128,000 tokens (128K)
Speed tierBalancedBalanced
VisionNoYes
Function callingYesYes
Extended thinkingNoNo
Prompt cachingYesYes
Batch APIYesNo
Release dateN/AMay 2026

Pricing matrix

Dollar rates only: hosts that list both models, per 1M tokens. For how much text fits, use the context section above — not this table.

ProviderGpt 4o Realtime Preview 2025 06 03 inGpt 4o Realtime Preview 2025 06 03 outGPT Chat Latest inGPT Chat Latest out
Openai$5.00/M$20.00/M——

Frequently asked questions

GPT Chat Latest has a larger context window: 400K tokens vs 128K. For long documents, large codebases, or extended agent sessions, the larger context window reduces the need to chunk inputs or summarize history.

Powered by Mem0

Use a smaller model.
Get better results.

Mem0 gives your AI long-term memory so you stop re-sending context on every call. That means you can use a smaller, faster, cheaper model — and still get better answers.

Calculate your savingsLearn about Mem0

Example: a multi-turn chat session

Without Mem0~128K tokens sent
Full history
Repeated info
Old context
With Mem0~20K tokens sent
Key memories
Current turn

80% less to send — works with any model