© 2020Two different methods, absolute and relative positioning, are used in determining point positions with GNSS techniques. Precise Point Positioning (PPP) technique, which is one of the absolute positioning methods, is a powerful position determination method. In this study, the accuracy of PPP has been investigated in terms of session durations, online web services, satellite visibility and urbanization. For this purpose, three of CORS-Tr stations were selected in residential, semi-residential and non-residential areas. Consecutive 31-day data of these stations for the year 2019 were downloaded from server. The 31-day consecutive coordinates were obtained by sending the downloaded RINEX data to AUSPOS. The average of these coordinates was considered as true quantity value. Then, the RINEX data were binned four groups as 1 h, 2 h, 4 h, 6 h. The binned data were evaluated with web-based online PPP services (CSRS-PPP, magicGNSS, APPS) and compared with the true quantity value. In conclusion, it was seen that the best result was obtained in the non-residential area and CSRS-PPP yielded the most accurate results for all session durations.