sRGB is recommended for both online display and Lab Prints!
For Web Display
For the most consistent display across all devices, we recommend saving your images in sRGB. sRGB is the standard for digital image display, and it will ensure your images are displayed correctly across all browsers on all devices. Other color spaces, such as Adobe RGB, may cause your images to look washed out in certain browsers.
Our Lab-Fulfillment partners recommend saving your files in sRGB. Adobe RGB will work in certain cases, though this color space is not as ideal as sRGB. For detailed information on color space recommendations it is best to refer to the website of your selected Lab. Each Lab has their own recommendation and calibration set up.