openai (Thu Nov 09 2023):

Pricing Page

The GPT-4 pricing model has been updated with a new 'GPT-4 Turbo' plan at $0.01 / 1K tokens for input and $0.03 / 1K tokens for output, and the 'GPT-3.5 Turbo' input price for the 16K context model decreased from $0.003 / 1K tokens to $0.0010 / 1K tokens, while the 'gpt-3.5-turbo' fine-tuning input usage price decreased from $0.0080 / 1K tokens to $0.0030 / 1K tokens.