JMeter Test Data Generator

Runs in browser Automation

Create datasets with the exact column layout your CSV Data Set Config expects, plus a snippet of the JMeter element configuration and variable names.

Privacy: This tool runs entirely in your browser. Your input never leaves your device.

How to use JMeter Test Data Generator

  1. Define the fields one per line (e.g. "username:username", "accountId:sequence:5000").
  2. Choose rows, delimiter, header row, sharing mode and the EOF behaviour.
  3. Click "Generate", then download the CSV next to your .jmx file.
  4. Copy the printed values into a CSV Data Set Config, or paste the JMX element into the test plan XML.
  5. Reference the variables in samplers as ${username}, ${password} and so on.

JMeter Test Data Generator features

  • Field schema DSL shared with the other feeder generators (sequence, username, token, pick…)
  • CSV with the exact column order your samplers reference as ${variable}
  • Printed CSV Data Set Config values: file, encoding, variable names, delimiter, quoting, recycle, stop-thread, sharing mode
  • Ready-to-paste JMX CSVDataSet element and a User Defined Variables element seeded with the first row
  • Warnings for contradictory EOF settings and small files shared by all threads
  • Reproducible datasets with a seed; synthetic values only

JMeter Test Data Generator example

Login dataset for a thread group

Input:

username:username
password:password:10
accountId:sequence:5000
Rows: 200 · Delimiter: , · Sharing: All threads

Output:

username,password,accountId
layla0001,Pw!x8Kq2Lm9a,5000
omar0002,Pw!Zr4Tb7Nc1,5001
…

CSV Data Set Config
  Filename: testdata.csv · Variable names: username,password,accountId
  Ignore first line: true · Recycle on EOF: true · Sharing mode: All threads

Frequently asked questions about JMeter Test Data Generator

What do I enter in CSV Data Set Config?

The tool prints every field: Filename, File encoding, Variable names, Ignore first line, Delimiter, Allow quoted data, Recycle on EOF, Stop thread on EOF and Sharing mode — copy them as-is.

Can I paste the JMX element directly?

Yes. The generated CSVDataSet XML (with its hashTree) can be pasted inside a Thread Group's hashTree in a .jmx file, or you can recreate it in the GUI from the printed values.

What is the User Defined Variables output for?

It turns the first row into default values so samplers keep working when the CSV is not attached yet.

Recycle vs Stop thread — which should I use?

Recycle = true loops the file for long tests; Recycle = false with Stop thread = true stops threads when unique data runs out. Both true makes Stop thread ineffective.

Are usernames unique?

Yes. Usernames combine a name with a zero-padded index, and sequence columns count up from the start value you set.

Technical notes

The JMX snippet mirrors the element JMeter 5.x writes itself (CSVDataSet with TestBeanGUI properties), so it can be pasted into a Thread Group's hashTree without further editing. Property names such as ignoreFirstLine, quotedData, recycle, shareMode and stopThread are the ones JMeter reads at load time.