FlagshipOpenAI

GPT Realtime

GPT Realtime is OpenAI's flagship model designed for real-time voice conversations, supporting both text and audio input/output with a 128K token context window.

Context 128K
Tier Flagship
Knowledge Oct 2024
Tools Supported
Modalities text, audio
Input from
$2.00 / 1M tokens
across 2 providers

API Pricing

Cheapest on OpenAI 40% below avg
ProviderInput / 1MOutput / 1MUpdated
OpenAI logo
OpenAIBatch
$2.00$8.004/14/2026
$4.00$16.004/9/2026
$4.00$16.004/14/2026

Prices updated daily. Last check: 4/14/2026

Model Details

General

Creator
OpenAI
Family
GPT Realtime
Tier
Flagship
Context Window
128K
Knowledge Cutoff
Oct 2024
Modalities
Text, Audio

Capabilities

Tool Calling
Yes
Open Source
No
Subtypes
Chat Completion

Strengths & Limitations

  • Native real-time audio input and output processing without separate TTS conversion
  • 128,000 token context window for extended conversation memory
  • Tool calling support enables API integration during voice conversations
  • Optimized for low-latency voice interactions and natural conversation flow
  • October 2024 knowledge cutoff provides relatively current information
  • Flagship-tier reasoning capabilities applied to voice-based interactions
  • Supports both text and audio modalities for flexible integration
  • Limited to audio and text modalities - no image or video input support
  • Proprietary model with no open-source weights available
  • Smaller context window compared to some competing flagship models
  • Specialized for voice use cases may not optimize for pure text tasks
  • Knowledge cutoff older than some competing models released in 2025-2026

Key Features

Real-time audio input and output processing
128K token context window
Tool calling with API integration
Chat completion interface
Low-latency voice conversation optimization
Native audio processing without TTS pipeline
Text and audio modality support
Streaming audio responses

About GPT Realtime

GPT Realtime is OpenAI's specialized flagship model built specifically for real-time voice interactions and conversational AI applications. As the first model in OpenAI's GPT Realtime family, it represents a dedicated approach to low-latency voice communication rather than being an extension of the GPT-4 series. The model operates with a 128,000 token context window and supports both text and audio modalities for input and output. The model's primary technical capability centers on real-time audio processing, enabling natural voice conversations with minimal latency. It maintains the context window size of 128K tokens and includes tool calling functionality, allowing it to interact with external APIs and services during conversations. The model's knowledge cutoff is October 2024, providing relatively current information for voice-based queries and interactions. GPT Realtime is positioned for applications requiring immediate voice response capabilities, such as voice assistants, real-time customer support, and interactive voice applications. Unlike text-focused models that require separate text-to-speech conversion, GPT Realtime handles audio natively, making it suitable for scenarios where conversation flow and response timing are critical factors.

Common Use Cases

GPT Realtime is designed for applications requiring immediate voice interaction capabilities, making it well-suited for voice assistants, real-time customer service systems, and interactive voice response applications. Its tool calling functionality enables voice-activated workflows that can integrate with external APIs and databases during conversations. The model excels in scenarios where conversation flow and response timing are critical, such as phone-based support systems, voice-controlled smart home devices, and real-time language practice applications. Its flagship-tier reasoning capabilities make it appropriate for complex voice-based queries that require multi-step thinking, while the 128K context window allows for extended conversations with maintained context.

Frequently Asked Questions

How much does GPT Realtime cost per million tokens?

GPT Realtime pricing varies by provider and usage type (audio vs text tokens may be priced differently). Check the pricing table above for current rates across all providers offering GPT Realtime access.

What is GPT Realtime best used for?

GPT Realtime is optimized for real-time voice conversations and applications requiring immediate audio response. It excels in voice assistants, customer service systems, phone-based support, and any scenario where natural conversation flow and low latency are important.

How does GPT Realtime differ from using GPT-4 with text-to-speech?

GPT Realtime processes audio natively without requiring separate text-to-speech conversion, resulting in lower latency and more natural conversation flow. It's specifically optimized for real-time voice interactions rather than text generation that gets converted to speech afterward.