Context Window

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Openai Gpt 5 Nano vs Openai Gpt Oss 120b

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

Openai Gpt 5 Nano

Tool calling

Context window

5M

5,000,000 tokens · ~3.8M words

Model page
Openai

Model

Openai Gpt Oss 120b

Tool calling

Context window

131K

131,072 tokens · ~98K 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.

Openai Gpt 5 Nano5M
Openai Gpt Oss 120b131K

Openai Gpt 5 Nano has about 38.1× the context window of the other in this pair.

Token calculator →Memory savings →

Openai Gpt 5 Nano has 3714% more context capacity (5000K vs 131K tokens). Openai Gpt Oss 120b is 0% cheaper on input.

Quick verdicts

Short takeaways — validate with your own workloads.

  • Long document processing

    Use Openai Gpt 5 Nano. Its 5000K context fits entire documents without chunking (vs 131K).

  • Long output (reports, code files)

    Use Openai Gpt Oss 120b. Its 32K 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.

SpecOpenai Gpt 5 NanoOpenai Gpt Oss 120b
Context window5,000,000 tokens (5000K)131,072 tokens (131K)
Max output tokens16,384 tokens (16K)32,768 tokens (32K)
Speed tierFastBalanced
VisionNoNo
Function callingYesYes
Extended thinkingNoYes
Prompt cachingNoNo
Batch APINoNo
Release dateN/AN/A

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.

ProviderOpenai Gpt 5 Nano inOpenai Gpt 5 Nano outOpenai Gpt Oss 120b inOpenai Gpt Oss 120b out
Aws Bedrock——$0.150/M$0.600/M
Snowflake$0.150/M$0.600/M——

Frequently asked questions

Openai Gpt 5 Nano has a larger context window: 5000K tokens vs 131K. For long documents, large codebases, or extended agent sessions, the larger context window reduces the need to chunk inputs or summarize history.

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