GPT-5.5 vs GPT-5.6 Terra

GPT-5.5 leads in 1 of 8 categories

Arena ELO

Tie

Cheaper

GPT-5.5

Faster

Tie

Detailed Comparison

Category	GPT-5.5	GPT-5.6 Terra
Provider	OpenAI	OpenAI
Context Window	128K	128K
Input Price ($/1M)	$5 WIN	$10
Output Price ($/1M)	$30	$30
Arena ELO	N/A	N/A
Coding	N/A	N/A
Reasoning	N/A	N/A
Speed (tokens/sec)	N/A	N/A
Open Source	No	No

Frequently Asked Questions

Which is cheaper, GPT-5.5 or GPT-5.6 Terra?

GPT-5.5 is approximately 13% cheaper than GPT-5.6 Terra per million tokens.

Which has a larger context window?

GPT-5.5 supports 128K context, while GPT-5.6 Terra supports 128K.

Is GPT-5.5 or GPT-5.6 Terra open source?

GPT-5.5 is proprietary. GPT-5.6 Terra is proprietary.

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