---
title: "Does setting a seed make OpenAI API responses reproducible?"  
description: "Does setting a seed make OpenAI API responses reproducible?"  
author: "Björn Ólafsson"  
published: 2026-10-25  
updated: 2026-10-25  
canonical: https://www.mindstick.com/forum/162923/does-setting-a-seed-make-openai-api-responses-reproducible  
category: "OpenAI API"  
tags: ["OpenAI", "api(s)", "Reproducibility", "testing"]  
reading_time: 1 minute  

---

# Does setting a seed make OpenAI API responses reproducible?

I’m trying to make a small evaluation set where I can compare prompt changes without output randomness muddying the results. If I set a seed in an OpenAI API request, how consistent should I expect the response to be across repeated calls?

I’m especially curious whether the same seed still helps when requests are sent at different times, or when a [model alias](https://www.mindstick.com/forum/162470/how-can-i-keep-openai-api-outputs-stable-when-a-model-alias-updates) may point to a newer snapshot. Is it reliable enough for regression tests, or should I treat it as a best-effort setting and allow for some variation?


---

Original Source: https://www.mindstick.com/forum/162923/does-setting-a-seed-make-openai-api-responses-reproducible

Copyright © MindStick Software Pvt. Ltd. This Markdown version is provided for developers, AI systems, and offline reading.