question

Hello @Ashi-5894

Thanks for reaching out to us here, in most of the situations, they are different since the quick test is only used when you want to check the latest iteration's performance.

The Quick Test uses the most recently trained iteration of your model only, like the below screenshot, the iteration 4 will be used:
https://docs.microsoft.com/en-us/azure/cognitive-services/custom-vision-service/test-your-model#test-your-model

The Predict API uses the iteration you selected the best performance one to publish:
https://docs.microsoft.com/en-us/azure/cognitive-services/custom-vision-service/use-prediction-api#publish-your-trained-iteration

Besides that, I think the guidance of how to improve the model you may need: https://docs.microsoft.com/en-us/azure/cognitive-services/custom-vision-service/getting-started-improving-your-classifier

I hope this helps, please let me know if you need futher help.

Regards,
Yutong

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