GPT-5.6 Terra Pro vs Inkling Small: side-by-side summary

GPT-5.6 Terra Pro and Inkling Small are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.

GPT-5.6 Terra Pro, from OpenAI, has a 1,050,000-token context window and is priced at $2/M tokens input, $12/M tokens output on OpenRouter.

Inkling Small, from thinkingmachines, has a 1,048,576-token context window and is priced at $0.45/M tokens input, $1.20/M tokens output on OpenRouter.

Context window

• GPT-5.6 Terra Pro: 1,050,000 tokens
• Inkling Small: 1,048,576 tokens

Price

• GPT-5.6 Terra Pro: $2/M tokens input, $12/M tokens output
• Inkling Small: $0.45/M tokens input, $1.20/M tokens output

Provided by

• GPT-5.6 Terra Pro: OpenAI
• Inkling Small: thinkingmachines

• GPT-5.6 Terra Pro model details, providers and pricing
• Inkling Small model details, providers and pricing