JSON command line

Batch Convert Files from the Windows Command Line

Convert supported files from PowerShell and return a clear result that another script can read.

By Osenpa Published Reviewed

Short answer

Open PowerShell in the standalone installation folder and convert one copied test file before you automate a folder. The Microsoft Store package does not include this command-line path.

When to use this method

The command-line interface, or CLI, is useful for repeatable local jobs and scripts. It does not turn unsupported input into a valid conversion and it should not expose passwords or private contents in logs.

Command-line behaviorSupported inputs, machine-readable results and the final output check.
How it works
The command accepts input paths, format, output, profile, collision mode, recursion and JSON output through a documented contract. It returns structured JSON and an exit code that a script can read.
Important limit
Shell success is not a fidelity check. A script must inspect the returned status and validate the created files.

What you need before using the command line

  • The standalone installation of Just Converter.
  • One copied test file and one writable output folder.
  • PowerShell, which is included with Windows.

The Microsoft Store package does not register a PowerShell command alias. This path-based workflow is for the standalone installation, where JustConverter.Cli.exe is in the cli folder.

Build a reliable command

Open PowerShell in the installation folder

In File Explorer, open the installation folder. Click its address bar, type powershell, and press Enter.

You should see: a PowerShell window whose prompt ends with the installation folder.

Check the command-line tool

Run .\cli\JustConverter.Cli.exe --help.

You should see: the convert command and its available options.

Convert one copied test file

.\cli\JustConverter.Cli.exe convert --input .\photo.png --format jpg --output .\converted. Replace photo.png with the copied test file you prepared.

You should see: a JPG in the converted folder and a success result in PowerShell.

Add recursion deliberately

Use recursive discovery only when nested folders are intended.

You should see: nested files in the result only when you supplied --recursive.

Choose collision behavior

Select rename, overwrite or skip explicitly instead of relying on an assumption.

You should see: each existing name handled by the option you chose.

Read JSON and exit codes

Add --json when another script needs a structured result for each file. Read the exit code separately because it summarizes the command as a whole.

You should see: one JSON result for every input file.

PowerShell showing a successful Just Converter JSON result with one input file and one output file.
Check the state and per-file status, then open the output path shown in the result.

Documented command shape

Replace each value in angle brackets, such as <path>, with the path, format, or other value your job needs.

Scroll the table horizontally on a narrow screen.

Part Example
Command .\cli\JustConverter.Cli.exe convert --input <path>... --format <format>
Optional output --output <directory> --profile <id>
Collision and discovery --collision rename|overwrite|skip --recursive
Machine-readable status --json
Exit codes 0 success; 1 usage or validation error; 2 no successful outputs; 3 partial success; 4 canceled; 5 required engine missing; 6 security or resource limit; 7 input/output or system failure

If the command fails or returns mixed results

Read the JSON result for each file before looking only at the final exit code. Check quoted paths, the chosen operation, output permissions, collision behavior and optional components. Do not treat a created file as proof of success until the result status and the file itself both pass inspection.

Watch for

Command-line automation mistakes

  • Logging passwords or private file contents
  • Using overwrite before checking the destination folder
  • Ignoring nonzero exit codes or per-file status
Verify the result

Command checkpoint

  • Before adding recursion or a scheduler, test one representative file. It should return exit code 0, include a successful JSON entry and create an output that opens correctly.
  • The result reports every name conflict.
  • If the exit code, JSON status or opened file disagrees, stop and inspect the command and per-file result.
Local file conversion queue in Just Converter
Step by step

Just Converter

Convert supported images, media, documents, and PDFs on your PC. Check compatibility first, reuse saved settings, watch folders, or the command line, and retry only failed files.