How much does GPT-3.5 Turbo Instruct cost on Zeplik?

Input tokens cost 16.5 credits per million and output tokens 22.0 credits per million (1 credit = $0.10; the raw provider rates are $1.50 and $2.00 per million). New accounts start with free credits.

How long can a conversation with GPT-3.5 Turbo Instruct be?

GPT-3.5 Turbo Instruct has a 4K-token context window (4,095 tokens), which covers the conversation plus any documents you attach.

Does GPT-3.5 Turbo Instruct support images and tools?

GPT-3.5 Turbo Instruct is text-only and does not support tool calling.

GPT-3.5 Turbo Instruct

Fast and light

OpenAI · Released September 2023 · Knowledge cutoff September 2021

This model is a variant of GPT-3.5 Turbo tuned for instructional prompts and omitting chat-related optimizations. Training data: up to Sep 2021.

It is part of OpenAI's GPT family, where Sol, Luna and Terra mark the current generation's capability tiers and Pro servings trade speed for deeper computation.

Facts and pricing

Provider: OpenAI
Context window: 4K tokens
Input price: 16.5 credits / 1M tokens ($1.50 raw)
Output price: 22.0 credits / 1M tokens ($2.00 raw)
Vision (image input): No
Tool calling: No
Extended reasoning: No

Credits are what Zeplik bills: 1 credit = $0.10, computed from the raw provider rate with a 1.10x margin. Raw prices shown per 1M tokens.

What GPT-3.5 Turbo Instruct is best for

High-volume everyday tasks where speed and cost matter: summaries, drafts, quick questions

Example prompts

Prompts that suit a fast and light model like GPT-3.5 Turbo Instruct:

Summarize this article in five bullet points
Rewrite this email to be shorter and friendlier
Give me ten name ideas for a hiking newsletter
Translate this paragraph to Spanish and keep the tone

OpenAI family

Model	Context	Input cr/M	Output cr/M	Released
GPT-6 Astra	1.1M	110	550	September 2026
GPT-6 Astra Pro	1.1M	110	550	September 2026
GPT-5.6 Luna Pro	1.1M	2.2	13.2	July 2026
GPT-5.6 Luna Pro (batch)	1.1M	1.1	6.6	July 2026
GPT-5.6 Luna (batch)	1.1M	1.1	6.6	July 2026
GPT-5.6 Luna	1.1M	2.2	13.2	July 2026
GPT-5.6 Terra Pro (batch)	1.1M	11.0	66.0	July 2026
GPT-5.6 Terra Pro	1.1M	22.0	132	July 2026
GPT-5.6 Terra	1.1M	22.0	132	July 2026
GPT-5.6 Terra (batch)	1.1M	11.0	66.0	July 2026

All 90 OpenAI models

Frequently asked questions

What is GPT-3.5 Turbo Instruct?: GPT-3.5 Turbo Instruct is an AI model by OpenAI. This model is a variant of GPT-3.5 Turbo tuned for instructional prompts and omitting chat-related optimizations. Training data: up to Sep 2021.
How much does GPT-3.5 Turbo Instruct cost on Zeplik?: Input tokens cost 16.5 credits per million and output tokens 22.0 credits per million (1 credit = $0.10; the raw provider rates are $1.50 and $2.00 per million). New accounts start with free credits.
How long can a conversation with GPT-3.5 Turbo Instruct be?: GPT-3.5 Turbo Instruct has a 4K-token context window (4,095 tokens), which covers the conversation plus any documents you attach.
Does GPT-3.5 Turbo Instruct support images and tools?: GPT-3.5 Turbo Instruct is text-only and does not support tool calling.

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