Work with files and images

What the binary field stores

One name is one file. You or the node choose the name, and the next step fetches the file by that name. The contents sit in data as base64. mimeType, fileName, and fileExtension tell later nodes what the file is and what to call it.

"binary": {
  "invoice": {
    "data": "<base64>",
    "mimeType": "application/pdf",
    "fileName": "invoice.pdf",
    "fileExtension": "pdf"
  }
}

Use a node that already speaks files

• Convert to File turns text, JSON, or a spreadsheet into a file on binary.
• Extract From File reads a file on binary back into rows or text.
• Read/Write Files from Disk reads and writes the machine disk when you self-host. A cloud instance does not have your disk.
• Compression, image edits, HTML, XML, and FTP each have their own nodes. They still take and return a binary slot.

On a self-hosted instance you can also choose where binary data is stored. That is instance storage, not a field inside json. Changing the store does not change the name a node uses.

Pinning and hidden execution data

If the output includes binary, that step cannot be pinned. To debug a file node you either let it produce the file each time, or prove the surrounding logic with data that has no file.

When execution data is hidden, binary is removed from the record. Opening the execution does not show the file. That does not undo the moment the node already passed the file onward or out to another system.