Throughout the world, many people contribute to the collaborative community of OpenStreetMap. For anyone who is interested in volunteering their time to map unmapped parts of the world, OSM Tasking Manager is a great way to find projects to assist on. OSM Tasking Manager ( is a mapping tool designed and built to coordinate mapping by Humanitarian OSM Team volunteers, making it easier for mappers to work together and avoiding conflicts in areas in the process of being mapped. The purpose of the tool is to divide up a mapping job into smaller tasks that can be completed rapidly. It shows which areas need to be mapped and which areas need the mapping validated. An area to be mapped is broken down into smaller areas on a grid so that mapping can be done in an organised way and distributed among volunteers throughout the world. As a result, mapping can also be completed quickly, which is especially vital in the context of an emergency. 

The Ramani Huria project has made use of the OSM Tasking Manager throughout our work, especially in when remote mapping to minimize the risk of overlapping work areas.  We have used the tool during Maptime events and mapping parties where we have mapped several wards of Dar es Salaam, including the subwards of: Makuburi; Kimanga; Kigamboni; Tungi; Vijibweni; Mjimwema; and Kibada. During OSM Geoweek 2015 events we facilitated at the University of Dar es Salaam and Ardhi University, we made use of OSM Tasking Manager to facilitate a mapathon including 150 volunteer mappers (see: 

The Ramani Huria OSM GeoWeek task on OSM Tasking Manager: 

Accessing OSM Tasking Manager

To start using OSM Tasking Manager, you will need an OpenStreetMap user account. To log in, click ‘login to OpenStreetMap’ in the top right corner of the page. If you don’t have an account, you will see a link to register or go directly to:

Authorising your OpenStreetMap account with OSM Tasking Manager 

Once you have logged you will be asked to authorise access to your account. Click ‘Save changes’ to allow OSM Tasking Manager to allow access and remember your account in the future.

Selecting a mapping task to contribute to

OSM Tasking Manager front page: 

Once you have logged in you will see a list of projects on the left hand side of the page, usually, the highest priority will be listed first. You can also search for specific tasks, including looking for mapping tasks by the city of the country. For example, search ‘Dar es Salaam’ and you will see all tasks for the city of Dar es Salaam. 

Project ‘#1389 – Missing Maps: Dar es Salaam – Ramani Huria2’: 

Once you have found the project you want to work on, click on the title of the task and you will open a page with details on that task. 

Each project will have five tabs on the left hand side of the page, and an image of the area to be mapped on the right hand side of the page. The tabs will give you all the information you need to start mapping, including:

  • Description – read the description carefully, this gives you an overview of the task and the goals of the mapping 
  • Instructions – this tells you what needs to be mapped (‘Entities to Map’) and the comments to put when uploading data to the OSM database (‘Changeset Comment’), often this will include hashtags to track mapping activities. It also will give a link to a dedicated preset if you are mapping in JOSM
  • Contribute – this section is where you will start your mapping by either selecting a task on the map or taking a task at random
  • Activity – this lists all the activity been done in this task by chronological order including who has contributed (with OSM username), the areas they have mapped, and date stamp. 
  • Stats – here you will find stats on how much of the task has been done and validated, as well as information on contributors, including their OSM username and number of sections done. 

Begin mapping a task

Select a task to start mapping: 

To begin mapping, select the ‘Contribute’ tab. Other mappers may have already begin to work on the map and you can see what areas need mapping or are in the process of being mapped by the colour of the square:

  • Squares with a yellow outline are currently being worked on – you cannot work on these areas until the person currently mapping unlocks that area
  • Grey squares are invalidated and haven’t yet been mapped
  • Yellow squares are done but not yet validated
  • Green squares are validated i.e. they have been completed

Selected an unmapped grey square to begin mapping a specific task on the map or click on the button to ‘Take a task at random’. 

When you select a square, details of the mapping in that area will be in the left hand side of the screen, as well as the specific task number. Click start mapping to begin. 

Editing the map

Selecting your prefered editing tool to start mapping

OSM Tasking Manager allows you to use your prefered editing tool to edit the task (e.g. JOSM, iD editor) and you can select this from the drop down list. You can view more details on how to edit with different options here.

When you start mapping an area, it will be locked for two hours, meaning no one else can work on this subtask while you are mapping. After this time, it will be automatically released so it’s important to make sure you know when this happens to avoid conflicts with other mappers on the same task. 

If the area is too big or complex for you to map within two hours, it’s a good idea to split the task into several smaller squares.

Finishing mapping and/or unlocking the task

If you have to stop mapping, or don’t have time to complete the area you are mapping within the time, it’s good practise to leave a comment about your progress and what remains to be mapped. You can add in as much information as is relevant, and then click ‘unlock’. 

If you have completed the task and mapped the entire area as requested, make sure you make the task as ‘complete’ so other mappers don’t have to come back and check through the area. Always leave any comments you think are relevant, including areas of the map you are unsure of. You can also tag in other OSM users by using the @ sign before their username, this is especially useful if you are working with other mappers or have a supervisor assisting you. 

Learn more

You can get additional help and tips on OSM Tasking Manager at The international volunteer mapping community is very helpful to other mappers so don’t hesitate to raise questions you have. You can also get live help in the OSM HOT IRC Channel #hot (details on how to access here:

Put your skills to use & meet other mappers

Come along to a Maptime event supported by Ramani Huria and put your new skills to practise. The community can also help you answer any questions you have about the tool. You can find details of the next Maptime event on our social media pages: Facebook and Twitter.

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