Our sample kits contain several respirator face masks to try.
Experiment with different sizes and shapes to find the respirator mask that fits you best and minimizes leakage. Here's a 3 minute video showing what to look for.
If you'd like to analyze the fit of your respirator with greater certainty, you can visit a 3rd party fit testing facility: simply google "mask fit testing near me." This service is called a Quantitative Fit Test. It usually costs $50-80. This is often a requirement for certain professions that wear an N95 in the workplace.