Crowdsourced mapping participation ranges from large, persistent online communities to short, intensive disaster campaigns. OpenStreetMap reported 10 million registered users in 2025-Q2, while Humanitarian OpenStreetMap Team (HOT) programs documented regional training, volunteer, and mapping totals across multiple reporting periods. These figures are not directly comparable: some are cumulative, some annual, and others describe a single project or response.
Contents
- OpenStreetMap’s global participation scale
- HOT’s cumulative reach and participation
- Asia-Pacific open mapping participation
- Eastern and Southern Africa participation
- Annual and COVID-19 mapping activity
- Mapathons, students, and disaster responses
OpenStreetMap’s global participation scale
The OpenStreetMap statistics page reported 10 million registered users in the second quarter of 2025. In the same quarter, it reported 2.25 million different user contributors. The distinction matters: registration counts describe the size of the account base, while different user contributors describe people who contributed during that quarter. Stats - OpenStreetMap Wiki, measurement period: 2025-Q2.
The database itself had reached 10 billion nodes on August 12, 2025. A node is a basic geographic element in the OpenStreetMap data model, so this figure describes accumulated map content rather than the number of people participating. Stats - OpenStreetMap Wiki, measurement date: 2025-08-12.
Earlier activity data illustrates the platform’s editing volume. OpenStreetMap recorded approximately 4 million map changes per day in the fourth quarter of 2021. That is an activity-rate measure, not a count of unique contributors, and it should not be treated as a current daily estimate. Stats - OpenStreetMap Wiki, measurement period: 2021-Q4.
| OpenStreetMap measure | Reported figure | Period or date |
|---|---|---|
| Registered users | 10 million | 2025-Q2 |
| Different user contributors | 2.25 million | 2025-Q2 |
| Nodes | 10 billion | August 12, 2025 |
| Map changes per day | Approximately 4 million | 2021-Q4 |
Together, these measures show why crowdsourced mapping participation needs more than one indicator. A community can have a large registered base, a smaller active contributor population, and an even larger accumulated data footprint.
HOT’s cumulative reach and participation
HOT’s 2023-2024 impact reporting gives a long-run view of humanitarian open mapping. Since its creation in 2010, HOT-supported mapping had reached areas home to 933.6 million people. The same report said 1.8 million people had been trained, and that Tasking Manager mappers had worked from more than 130 countries.
The report recorded 22,100 Tasking Manager mappers since the organization’s creation and mapping work covering 335,400 places. These are cumulative figures reported in the 2023-2024 impact report, not a count of people active in a single year. Impact Report 2023-2024 - Humanitarian OpenStreetMap Team, reported period: since 2010, as reported in 2023-2024.
Community support was also quantified. HOT had issued 171 community grants since its creation. During the 2023-2024 reporting period, it supported 46 disaster responses. The grant total is cumulative, while the disaster-response figure is specific to the reporting period, so they describe different dimensions of participation and organizational activity.
The cumulative numbers combine people, places, countries, grants, and affected population reach. They should therefore be read as a portfolio of participation indicators rather than summed into one total. A person trained, a Tasking Manager mapper, and a resident of a mapped area are not interchangeable categories.
Asia-Pacific open mapping participation
HOT’s Asia-Pacific Hub had reached 32 countries since its establishment in early 2021, according to the 2023-2024 impact report. It had supported 12 projects, built 107 partnerships, and trained 3,035 people over that period. The hub also reported 139,000 mapping volunteers and Tasking Manager mapping for areas home to 290.2 million people. Impact Report 2023-2024 - Humanitarian OpenStreetMap Team, reported period: since early 2021, as reported in 2023-2024.
The hub’s Open Mapping Guru project provides a more specific project-level view. It mapped and validated 1.52 million buildings and 49,000 km of roads. The project involved 4,296 mappers, had more than 240 Gurus, and trained more than 1,700 people. These counts refer to different roles or outputs within the same project and should not be added together as unique participants.
Participation also took a team-based form. More than 50 Guru-led teams joined the hub’s month-long Climate Change Challenge. The project and challenge figures show how participation can be organized through local leadership, training, validation, and time-bounded campaigns rather than only through a general contributor pool.
Eastern and Southern Africa participation
HOT’s Eastern and Southern Africa Hub had reached 22 countries since its creation in early 2021. In the 2023-2024 impact reporting, the hub recorded 32 supported projects, 19 partnerships, and 8,033 people trained. It reported 126,100 mapping volunteers and Tasking Manager mapping for areas home to 244.9 million people. Impact Report 2023-2024 - Humanitarian OpenStreetMap Team, reported period: since early 2021, as reported in 2023-2024.
The hub’s project outputs included 1.075 million buildings mapped in its public-health mapping program and 5,757 km of roads mapped in its early-warning mapping program. A separate public-health mapping program figure recorded 82,944 buildings and 2,239 km of roads. Because the report presents these as named program measures, they should remain separate rather than being combined without a defined scope.
Regional comparisons need the same caution. The Asia-Pacific Hub reported more countries reached, partnerships, trained people, volunteers, and mapped-population reach in its cumulative measures, while Eastern and Southern Africa reported its own country, project, training, volunteer, and reach totals. Differences may reflect program scope, geography, and reporting definitions; the supplied figures do not establish a performance ranking.
Annual and COVID-19 mapping activity
HOT’s 2019 annual report recorded 51,606 people contributing to the map. It also reported 2,400 mapping projects, 2 million tasks mapped, 367,404 km of road mapped, and 12.5 million buildings mapped during 2019. Annual Report 2019 - Humanitarian OpenStreetMap Team, measurement period: 2019.
The 2020-21 annual report described a concentrated COVID-19 mapping effort. More than 26,000 remote mappers contributed to COVID-19 Tasking Manager projects. Those projects received almost 5.4 million map features, including nearly 4.8 million buildings and more than 122,000 km of road. Annual Report 2020-21 - Humanitarian OpenStreetMap Team, measurement period: 2020-21.
One campaign-level figure from that period identifies Accenture volunteers as adding 38,265 buildings during a March 2020 mapping campaign. It is a contribution count for that campaign, not a total for all corporate volunteers or all COVID-19 mapping. Annual Report 2020-21 - Humanitarian OpenStreetMap Team, measurement period: March 2020.
| Program or period | Participation measure | Mapping output measure |
|---|---|---|
| HOT annual activity, 2019 | 51,606 contributors | 12.5 million buildings; 367,404 km of roads |
| COVID-19 Tasking Manager projects, 2020-21 | More than 26,000 remote mappers | Almost 5.4 million features; more than 122,000 km of roads |
| Accenture campaign | Volunteers identified by campaign | 38,265 buildings, March 2020 |
The annual figures show two different patterns: broad recurring program activity in 2019 and a focused response around COVID-19 in 2020-21. Since the periods and project boundaries differ, the values are best used as descriptive benchmarks rather than as a time series with a single growth rate.
Mapathons, students, and disaster responses
Crowd2Map Tanzania recruited more than 1,500 online volunteers in 2016. Those volunteers remotely mapped more than 50,000 km², added more than 1 million buildings, and added 64,000 km of roads. 2016 Annual Report - Humanitarian OpenStreetMap Team, measurement period: 2016.
YouthMappers had 57 university chapters in 19 countries in 2016, with approximately 2,000 student mappers. YouthMappers-tagged contributions generated over 6 million OpenStreetMap edits in the second half of 2016. The chapter and student figures describe the network, while the edit figure describes activity. 2016 Annual Report - Humanitarian OpenStreetMap Team, measurement periods: 2016 and 2016-H2.
The Nepal earthquake response demonstrates rapid mobilization. It had 3,679 mappers making more than 3 million edits within five days, mapped 6,214 square miles in detail, and attracted more than 8,000 volunteer contributors worldwide. One-third of contributors to the response were new mappers. 2015 Annual Report - Humanitarian OpenStreetMap Team, measurement periods: April-May 2015 and 2015.
More recent national mapathons provide smaller, bounded examples. The first Ecuador National Annual Mapathon brought together 1,039 participants in 2024, mapped 15,388 buildings, and mapped 101 km of infrastructure. Anticipatory Annual Mapathons: Innovation and Collaboration to Close Mapping Gaps in Latin America and the Caribbean, measurement period: 2024.
The Morocco and Libya disaster campaigns in September 2023 involved approximately 1,600 mappers, created approximately 220,000 buildings, and created approximately 5,000 km of roads. Update on disaster response activations for Morocco and Libya, measurement period: September 2023.
Colombia’s first National Mapathon brought together 200 participants in 2024. It mapped 26,111 buildings and 28 km of roads. Closure of Colombia’s National Mapathon 2025, measurement period: 2024.
These examples show the range of participation formats: university chapters, remote volunteer recruitment, national mapathons, and emergency activations. Their reported counts are useful when the unit and period remain visible—participants, mappers, edits, buildings, roads, and mapped area measure different parts of crowdsourced mapping participation.