How the ATP and WTA tours called lines, 2017 to 2026

In 2026, 22 of 22 ATP events and 10 of 10 WTA events in the dataset called every line electronically. In 2017 it was 1 of 11 and 0 of 10.

ATP01020302017: Electronic on every court, 1 of 11 events2017: Line judges and challenges, 7 of 11 events2017: Line judges only, 3 of 11 events'172018: Electronic on every court, 1 of 11 events2018: Line judges and challenges, 7 of 11 events2018: Line judges only, 3 of 11 events'182019: Electronic on every court, 1 of 11 events2019: Line judges and challenges, 7 of 11 events2019: Line judges only, 3 of 11 events'192020: Electronic on every court, 2 of 4 events2020: No trusted source, 2 of 4 events'202021: Electronic on every court, 5 of 10 events2021: Line judges and challenges, 1 of 10 events2021: Line judges only, 1 of 10 events2021: No trusted source, 3 of 10 events'212022: Electronic on every court, 2 of 10 events2022: Line judges only, 1 of 10 events2022: No trusted source, 7 of 10 events'222023: Electronic on every court, 2 of 11 events2023: Line judges only, 1 of 11 events2023: No trusted source, 8 of 11 events'232024: Electronic on every court, 5 of 11 events2024: Line judges and challenges, 1 of 11 events2024: Line judges only, 2 of 11 events2024: No trusted source, 3 of 11 events'242025: Electronic on every court, 27 of 27 events'252026: Electronic on every court, 22 of 22 events'26WTA01020302017: Line judges and challenges, 8 of 10 events2017: Line judges only, 1 of 10 events2017: No trusted source, 1 of 10 events'172018: Line judges and challenges, 8 of 10 events2018: Line judges only, 2 of 10 events'182019: Line judges and challenges, 8 of 10 events2019: Line judges only, 1 of 10 events2019: No trusted source, 1 of 10 events'192020: Electronic on every court, 1 of 3 events2020: Line judges and challenges, 1 of 3 events2020: No trusted source, 1 of 3 events'202021: Electronic on every court, 4 of 8 events2021: Line judges and challenges, 1 of 8 events2021: No trusted source, 3 of 8 events'212022: Electronic on every court, 3 of 9 events2022: No trusted source, 6 of 9 events'222023: Electronic on every court, 1 of 10 events2023: No trusted source, 9 of 10 events'232024: Electronic on every court, 3 of 11 events2024: Line judges and challenges, 1 of 11 events2024: No trusted source, 7 of 11 events'242025: Electronic on every court, 2 of 11 events2025: No trusted source, 9 of 11 events'252026: Electronic on every court, 10 of 10 events'26ATP01020302017: Electronic on every court, 1 of 11 events2017: Line judges and challenges, 7 of 11 events2017: Line judges only, 3 of 11 events'172018: Electronic on every court, 1 of 11 events2018: Line judges and challenges, 7 of 11 events2018: Line judges only, 3 of 11 events'182019: Electronic on every court, 1 of 11 events2019: Line judges and challenges, 7 of 11 events2019: Line judges only, 3 of 11 events'192020: Electronic on every court, 2 of 4 events2020: No trusted source, 2 of 4 events'202021: Electronic on every court, 5 of 10 events2021: Line judges and challenges, 1 of 10 events2021: Line judges only, 1 of 10 events2021: No trusted source, 3 of 10 events'212022: Electronic on every court, 2 of 10 events2022: Line judges only, 1 of 10 events2022: No trusted source, 7 of 10 events'222023: Electronic on every court, 2 of 11 events2023: Line judges only, 1 of 11 events2023: No trusted source, 8 of 11 events'232024: Electronic on every court, 5 of 11 events2024: Line judges and challenges, 1 of 11 events2024: Line judges only, 2 of 11 events2024: No trusted source, 3 of 11 events'242025: Electronic on every court, 27 of 27 events'252026: Electronic on every court, 22 of 22 events'26WTA01020302017: Line judges and challenges, 8 of 10 events2017: Line judges only, 1 of 10 events2017: No trusted source, 1 of 10 events'172018: Line judges and challenges, 8 of 10 events2018: Line judges only, 2 of 10 events'182019: Line judges and challenges, 8 of 10 events2019: Line judges only, 1 of 10 events2019: No trusted source, 1 of 10 events'192020: Electronic on every court, 1 of 3 events2020: Line judges and challenges, 1 of 3 events2020: No trusted source, 1 of 3 events'202021: Electronic on every court, 4 of 8 events2021: Line judges and challenges, 1 of 8 events2021: No trusted source, 3 of 8 events'212022: Electronic on every court, 3 of 9 events2022: No trusted source, 6 of 9 events'222023: Electronic on every court, 1 of 10 events2023: No trusted source, 9 of 10 events'232024: Electronic on every court, 3 of 11 events2024: Line judges and challenges, 1 of 11 events2024: No trusted source, 7 of 11 events'242025: Electronic on every court, 2 of 11 events2025: No trusted source, 9 of 11 events'252026: Electronic on every court, 10 of 10 events'26

Columns count the events in the dataset for each tour and season. 60 of the 220 have no trusted source. The dataset covers ATP 500 events in 2025 and 2026 only.

Show the numbers as a table

Events that were not held have no row. That covers Wimbledon 2020, the other events cancelled in 2020, the events in China from 2020 to 2022, and Wuhan in 2023. Events still to be played after 22 October 2026 are also left out.

ATP events by season
SeasonElectronic on every courtElectronic on some courtsLine judges and challengesLine judges onlyNo trusted sourceAll events
20171073011
20181073011
20191073011
2020200024
20215011310
20222001710
20232001811
20245012311
202527000027
202622000022
WTA events by season
SeasonElectronic on every courtElectronic on some courtsLine judges and challengesLine judges onlyNo trusted sourceAll events
20170081110
20180082010
20190081110
2020101013
2021401038
2022300069
20231000910
20243010711
20252000911
202610000010

Source: Live Tennis API, tennis line-calling dataset. CC BY 4.0. Version 1.0.1, data to 22 October 2026.