Hello @Adi Cohen Thank you for contacting us on Microsoft Q&A platform. Happy to answer any questions you may have!
Based on the details provided in the description, I understand that you are using the Azure Retail Prices API to programmatically fetch VMs pricing and would like to know which OS is installed (Windows or Linux) and its types.
The Retail price for VM pricing, the product name will define. If it includes Windows, then the meter is with Windows license. If it does not have Windows, then it is Linux. For DevTest workload, the Windows OS is not charged so for Dev/Test workload even with Windows OS will be billed on Linux meter itself.
Hope this answers your question. Please write back to us if you have any further questions.
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