GPT-3.5 Turbo 16k

Name: GPT-3.5 Turbo 16k
Author: OpenAI

Released

2023-06-13

Last refreshed

2026-10-14

Status

Researched 8d ago

DeprecatedProprietaryCommercial use: conditionalClassificationJSON / Tool use

GPT-3.5 Turbo 16k is a legacy integration reference; keep it only while you identify a current replacement.

OpenAI releases · 44 in the last 12 monthsChangelog →

Specifications

Family: GPT-3.5
Released: 2023-06-13
Context: 16K
Parameters: 20B
Architecture: Decoder Only
Knowledge cutoff: 2021-09
Specialization: general
Openness: Proprietary
License: ProprietaryCommercial use: conditional
Weights: Not released
Code: Unknown
Training: Fine-tuned

Created by

OpenAI

Cutting-edge research and development.

San Francisco, California, United States

Founded 2015

Website

Pricing

Output / 1M

$4.00

Input / 1M

$3.00

Cheapest of 1 route · OpenRouter

Providers(1)

OpenRouter

View 1 provider route

About

GPT-3.5 Turbo 16k, developed by OpenAI, is an advanced language model featuring a significantly enhanced context window of 16,384 tokens—four times larger than its predecessor's 4,096 tokens 245. This extension allows it to process and comprehend extended texts, up to approximately 20 pages, in a single interaction, while maintaining the speed and efficiency of earlier versions 10. Although it is a chat-centric model not compatible with the completions endpoint 8, it remains highly effective for tasks requiring prolonged relevance and coherence through OpenAI's API 46.

Providers(1)

Compare API pricing across 1 tracked provider route for input and output tokens, batch, and cached reads when available.

Provider	Input / 1M	Output / 1M	Route
OpenRouter	$3.00	$4.00	Serverless

Deprecated provider routes(2)

Provider	Status	Catalog ID
Azure OpenAI	Deprecated	—
Salesforce Models API	Deprecated	—

Available via routers & gateways(5)

LiteLLM

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Microsoft Azure AI Foundry's native model router that uses a trained ML model to route each prompt in real time to the optimal Azure-hosted model, with Balanced/Cost/Quality mode selection and automatic failover.

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Gateway

Observability-first AI gateway with routing, caching, rate limiting, and request tracing; Apache 2.0 open-source core with a managed hosted tier for logging and analytics.

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Kong AI Gateway

Gateway

Multi-LLM AI gateway built on Kong Gateway 3.x, adding semantic routing, load balancing, guardrails, and MCP traffic analytics as plugins over Kong's existing API management platform.

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