Yes, it will work on your mid 2012 MacBook Pro. While the recommendations were up to 8GB, I read a few other reviews here on Amazon that recommended 16GB and decided to give it a go to try. I'm so happy I did. I am very happy with the purchase. Very easy to install and 4x upgrade from 4GB to 16GB. I also changed HD to SSD (also purchased through Amazon: https://www.amazon.com/Crucial-MX300-Internal-Solid-State/dp/B01IAGSDUE/ref=sr_1_1?s=pc&ie=UTF8&qid=1487562890&sr=1 - 1&keywords=Crucial+MX300+1TB+SATA+2.5+inch+internal+SSD+drive+drive+-+CT1050MX300SSD1). More than happy with my new car. I highly recommend it!
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