GPT-6 Astra Pro vs GLM 5.3: side-by-side summary

GPT-6 Astra Pro and GLM 5.3 are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.

GPT-6 Astra Pro, from OpenAI, has a 1,050,000-token context window and is priced at $10/M tokens input, $50/M tokens output on OpenRouter.

GLM 5.3, from Z.ai, has a 1,310,720-token context window and is priced at $1.15/M tokens input, $3.50/M tokens output on OpenRouter.

Context window

• GPT-6 Astra Pro: 1,050,000 tokens
• GLM 5.3: 1,310,720 tokens

Price

• GPT-6 Astra Pro: $10/M tokens input, $50/M tokens output
• GLM 5.3: $1.15/M tokens input, $3.50/M tokens output

Provided by

• GPT-6 Astra Pro: OpenAI
• GLM 5.3: Z.ai

• GPT-6 Astra Pro model details, providers and pricing
• GLM 5.3 model details, providers and pricing