I have performed an HRMS experiment on many compounds and obtained the following;

Compound 1. calculated [M+H]+: 554.2073  

Found [M+H]+:554.2135

compound 2. calculated [M+H]+: 588.1684

Found [M+H]+: 588.1481

There is some deviation from the calculated data, so is this deviation acceptable, if not, then what is the acceptable deviation range. Finally, does this tell me anything about the purity of the compound? Nmr of compounds looks fine. Anyone has an idea about this please let me know.

Thanks