how to estimate the iPhone video (mov) format to mp3 format in elemental calculator in AWS

Thanks for the question. You can find the AWS Elemental MediaConvert pricing here https://aws.amazon.com/mediaconvert/pricing/

If you are only creating MP3 outputs, then that would be considered Basic Tier transcoding. Audio only costs for Basic Tier is listed as $0.003/min. If the MP3 audio output is part of a large transcode with video outputs, it may land in the Professional Tier pricing, listed as $0.005/min. The Basic vs Tier features are listed at the bottom of the pricing link.