Whenever I export an editted photo and open it on my mac the photos look grainy and much lower quality than what I had in lightroom before the export. Putting these photos on social media or looking at them on my phone they seem to be back to the quality they were before the export.
Export settings are:
6000 pixels longside
Standard screen sharpening
How can I have the images retain good quality when being viewed on my mac? I want to make sure anyone I send the photos to can see good quality photos.
Your problem is ironically that you are exporting to way too high quality for social media sites. The image you are exporting has to be downscaled to the display size and the downscaling (and recompression) algorithm used by most social media sites is not very good and will make the image look blurry or grainy. What you should do if you are going to social media is to export to a smaller size (e.g. 1800 pixels on the long side is more than enough. For instagram you need 1024 pixel images or 2048 pixels. facebook and twitter do around 1800 pixels). You also want to lower the quality to around 85. Anything higher just wastes bandwidth and can actually trigger the social media platforms to recompress your image to save on their bandwidth. They usually use terrible quality settings when they do this.
So export top jpeg, 1800 pixels on the long side, 80% quality (about). standard sharpening and sRGB. That should look best everywhere.