__property

Also documented in context in the full Functions and Variables reference.

TL;DR: __property reads a JMeter property (JVM-level config, not a per-thread variable) — the standard way to make a test plan configurable from outside without editing the .jmx (environment name, base URL, feature flags).

The property function returns the value of a JMeter property. If the property value cannot be found, and no default has been supplied, it returns the property name. When supplying a default value, there is no need to provide a function name - the parameter can be set to null, and it will be ignored.

For example:

• \${__property(user.dir)} - return value of user.dir
• \${__property(user.dir,UDIR)} - return value of user.dir and save in UDIR
• \${__property(abcd,ABCD,atod)} - return value of property abcd (or “atod” if not defined) and save in ABCD
• \${__property(abcd,,atod)} - return value of property abcd (or “atod” if not defined) but don’t save it

Name	Required	Description
Property Name	Yes	The property name to be retrieved.
Variable Name	No	A reference name for reusing the value computed by this function.
Default Value	No	The default value for the property.

Example

${__property(user.dir)}              → value of the "user.dir" JMeter property
${__property(abcd,ABCD,atod)}        → value of "abcd" (or "atod" default), saved to variable ABCD
${__property(abcd,,atod)}            → same lookup, without saving to a variable

For properties set specifically via the -J CLI flag, __P is a shorter alternative. See the Properties Reference for JMeter’s built-in tuning properties and the CLI Command Builder for constructing -J flags.

Related

• Functions and Variables Guide
• Regex Extractor Builder
• Properties Reference
• Properties Cheatsheet
• Full Functions Reference
• Component Reference