Configure run or build numbers

Azure DevOps Services | Azure DevOps Server 2022 - Azure DevOps Server 2019

You can customize how your pipeline runs are numbered. The default value for run number is $(Date:yyyyMMdd).$(Rev:r).

In Azure DevOps $(Rev:r) is a special variable format that only works in the build number field. When a build is completed, if nothing else in the build number has changed, the Rev integer value increases by one.

$(Rev:r) resets when you change part of the build number. For example, if you've configured your build number format as $(Build.DefinitionName)_$(Date:yyyyMMdd).$(Rev:r), then the build number will reset when the date changes the next day. If your build number is MyBuild_20230621.1, the next build number that day is MyBuild_20230621.2. The next day, the build number is MyBuild_20230622.1.

If your build number format is 1.0.$(Rev:r), then the build number resets to 1.0.1 when you change part of the number. For example, if your last build number was 1.0.3, and you change the build number to 1.1.$(Rev:r) to indicate a version change, the next build number is 1.1.1.

In YAML, this property is called name and must be at the root level of a pipeline.


Items specified at the root level of a YAML file are pipeline properties.

If not specified, your run is given a unique integer as its name. You can give runs much more useful names that are meaningful to your team. You can use a combination of tokens, variables, and underscore characters. The name property doesn't work in template files.

name: $(TeamProject)_$(Build.DefinitionName)_$(SourceBranchName)_$(Date:yyyyMMdd).$(Rev:r)

  - script: echo '$(Build.BuildNumber)' # outputs customized build number like project_def_master_20200828.1

YAML builds aren't yet available on TFS.


At the time, a run is started:

  • Project name: Fabrikam

  • Pipeline name: CIBuild

  • Branch: main

  • Build ID/Run ID: 752

  • Date: May 5, 2019.

  • Time: 9:07:03 PM.

  • One run completed earlier today.

If you specify this build number format:


Then the second run on this day would be named: Fabrikam_CIBuild_main_20190505.2


The following table shows how each token is resolved based on the previous example. You can use these tokens only to define a run number; they don't work anywhere else in your pipeline.

Token Example replacement value
$(Build.DefinitionName) CIBuild

Note: The pipeline name must not contain invalid or whitespace characters.
$(Build.BuildId) 752

$(Build.BuildId) is an internal immutable ID that is also referred to as the Run ID. It's unique across the organization.
$(DayOfMonth) 5
$(DayOfYear) 217
$(Hours) 21
$(Minutes) 7
$(Month) 8
$(Rev:r) 2 (The third run is 3, and so on.)

Use $(Rev:r) to ensure that every completed build has a unique name. When a build starts, if nothing else in the build number has changed, the Rev integer value is incremented by one.

If you want to show prefix zeros in the number, you can add more 'r' characters. For example, specify $(Rev:rr) if you want the Rev number to begin with 01, 02, and so on. If you use a zero-padded Rev as part of a version numbering scheme, note that some pipeline tasks or popular tools, like NuGet packages, remove the leading zeros, which cause a version number mismatch in the artifacts that are produced.
$(Date:yyyyMMdd) 20090824

You can specify other date formats such as $(Date:MMddyy)
$(Seconds) 3
$(SourceBranchName) main
$(TeamProject) Fabrikam
$(Year:yy) 09
$(Year:yyyy) 2009


You can also use user-defined and predefined variables that have a scope of "All" in your number. For example, if you've defined My.Variable, you could specify the following number format:


The first four variables are predefined. My.Variable is defined by you on the variables tab.


If you use an expression to set the build number, you can't use some tokens because their values aren't set at the time expressions are evaluated. These tokens include $(Build.BuildId), $(Build.BuildURL), and $(Build.BuildNumber).


How large can a run number be and what characters can I use?

Runs may be up to 255 characters. Characters that aren't allowed include ", /, :, <, >, ', |, ?, @, and *. You can't end with a ..

In what time zone are the build number time values expressed?

The time zone is UTC.

The time zone is the same as the time zone of the operating system of the machine where you're running your application tier server.

How can you reference the run number variable within a script?

The run number variable can be called with $(Build.BuildNumber). You can define a new variable that includes the run number or call the run number directly. In this example, $(MyRunNumber) is a new variable that includes the run number.

# Set MyRunNumber
  MyRunNumber: '1.0.0-CI+$(Build.BuildNumber)'

- script: echo $(MyRunNumber) # display MyRunNumber
- script: echo $(Build.BuildNumber) #display Run Number

How can I set the build number dynamically with conditions?

You can use variables as part of your run number. In this example, the variable why changes depending on the Build.Reason and is used as part of the run number.

  - name: why
    ${{ if eq(variables['Build.Reason'], 'PullRequest') }}:
      value: pr
    ${{ elseif eq(variables['Build.Reason'], 'Manual' ) }}:
      value: manual
    ${{ elseif eq(variables['Build.Reason'], 'IndividualCI' ) }}:
      value: indivci
    ${{ else }}:
      value: other

name: $(TeamProject)_$(SourceBranchName)_$(why)_$(Date:yyyyMMdd).$(Rev:.r)

  vmImage: 'ubuntu-latest'

- script: echo '$(Build.BuildNumber)' ## output run number