Why are there /meta/read charges in my billing?

The /meta/read charges appear in your monthly billing, because Transloadit by default automatically extracts metadata from your uploaded files and the files produced by other Steps. This is a standard part of file processing that helps enable features like using ${file.meta.width}, ${file.meta.duration}, and other extracted metadata variables in your Assembly Instructions.

How much do /meta/read charges cost?

Standard metadata extraction counts 1% of the file size as billable processing bytes for uploaded files and each tracked Step's outputs. For a single extraction:

• A 100 MB file would incur 1 MB in metadata extraction charges
• A 1 GB file would incur 10 MB in metadata extraction charges

Optional, more expensive metadata can incur additional charges. See the output_meta parameter in the Robot documentation for details.

How can I avoid /meta/read charges?

You can opt out of automatic metadata extraction by adding "output_meta": false to each Step whose output does not need extracted metadata, including your upload Step:

{
  "steps": {
    ":original": {
      "robot": "/upload/handle",
      "output_meta": false
    },
    "resize": {
      "use": ":original",
      "robot": "/image/resize",
      "format": "jpg",
      "width": 200,
      "height": 200,
      "output_meta": false
    }
  }
}

When should I keep metadata extraction enabled?

Many processing Templates require metadata extraction. It's important for:

• letting Robots ignore file types they cannot handle
• using extracted file metadata variables in your Assembly Instructions (like ${file.meta.width} and ${file.meta.duration})
• filtering files based on metadata properties
• storing metadata tags with your files
• generating dynamic file paths based on extracted metadata

File identifiers and names, such as ${file.id} and ${file.name}, are available without metadata extraction. For example, this Template uses the uploaded file's name without extracting metadata:

{
  "steps": {
    ":original": {
      "robot": "/upload/handle",
      "output_meta": false
    },
    "stored": {
      "use": ":original",
      "robot": "/s3/store",
      "path": "/uploads/${file.id}_${file.name}",
      "output_meta": false
    }
  }
}

When can I safely disable metadata extraction?

You can disable metadata extraction when:

• You don't use extracted file.meta.* variables in subsequent Steps
• Your paths and names use fixed values, supplied fields, or file identifiers and names
• You don't need to filter or sort files based on extracted metadata

Example for a single uploaded file that doesn't need metadata (fields is provided when creating the Assembly):

{
  "steps": {
    "uploaded": {
      "robot": "/upload/handle",
      "output_meta": false
    },
    "exported": {
      "use": "uploaded",
      "robot": "/s3/store",
      "path": "${fields.output_path}",
      "output_meta": false
    }
  }
}