Is OpenAI GPT-OSS 20b or Anthropic: Claude Opus 4.5 cheaper?

OpenAI GPT-OSS 20b is cheaper on output tokens ($0.20 vs $25.00 per 1M).

Which has the larger context window, OpenAI GPT-OSS 20b or Anthropic: Claude Opus 4.5?

Anthropic: Claude Opus 4.5 has the larger context window (200K tokens).

OpenAI GPT-OSS 20b vs Anthropic: Claude Opus 4.5

OpenAI GPT-OSS 20b is cheaper on output tokens, while Anthropic: Claude Opus 4.5 offers a larger context window. Choose OpenAI GPT-OSS 20b or Anthropic: Claude Opus 4.5 based on the trade-off between cost, context, and the benchmarks that matter for your use case.

Spec	OpenAI GPT-OSS 20b	Anthropic: Claude Opus 4.5
Provider	Helicone	Helicone
Input / 1M tokens	$0.05	$5.00
Output / 1M tokens	$0.20	$25.00
Context window	131K	200K
Parameters	21B	—
Open weights	No	No
Released	Jun 2024	Nov 2025

OpenAI GPT-OSS 20b details →Anthropic: Claude Opus 4.5 details →

FAQ

Pricing is indicative — confirm with the provider before production use. Highlighted values indicate the better figure for that row.