File Utils

Convert between base64 strings and files.

Overview

The File Utils node converts files to base64-encoded strings and vice versa. Use it to:

• Decode base64 data from an API response into a downloadable file
• Encode a file as base64 for embedding in a JSON payload or API call
• Bridge between text-based workflows and file-based workflows

Parameters

Parameter	Description	Required
Operation	Base64 to File or File to Base64	Yes

The remaining parameters depend on the selected operation.

Base64 to File

Converts a base64-encoded string into a file.

Parameter	Description	Required
Base64 Content	The base64-encoded string. Supports expressions.	Yes
Filename	Name for the output file (e.g. report.pdf). Supports expressions.	Yes
File Destination	Where to save the created file.	Yes

{{ $item.data.base64String }}

File to Base64

Converts a file into a base64-encoded string.

Parameter	Description	Required
File	The file to convert. Supports expressions.	Yes

{{ $item }}
{{ $item.data.file }}

Files from any source (Google Drive, OneDrive, temporary bucket) are supported. The node copies them to a temporary bucket before encoding.

Output

Base64 to File

Produces an item with a file property containing the created file:

{
  "file": {
    "type": "fileData",
    "name": "report.pdf",
    "fileInfo": { "type": "temporaryLidoBucket", "bucketFileName": "..." }
  }
}

File to Base64

Produces an item with the base64 string and original filename:

{
  "base64": "JVBERi0xLjQK...",
  "filename": "report.pdf"
}

Examples

Decode an API Response

An API returns a PDF as base64. Convert it to a file for downstream processing:

[Call URL (get PDF)] → [File Utils (Base64 to File)] → [Copy File (to Google Drive)]

• Operation: Base64 to File
• Base64 Content: {{ $item.data.pdfContent }}
• Filename: {{ $item.data.documentName }}.pdf

Encode a File for an API Call

Send a file as base64 in a JSON request body:

[Get Table (file column)] → [File Utils (File to Base64)] → [Call URL (POST to API)]

• Operation: File to Base64
• File: {{ $item }}

Then in Call URL, reference {{ $item.data.base64 }} in the request body.

Round-Trip Conversion

Convert to base64, process the string, then convert back:

[Trigger] → [File Utils (File to Base64)] → [JS Code (modify)] → [File Utils (Base64 to File)]

Tips

• The node processes items one at a time — each input item produces one output item
• Base64 encoding increases data size by roughly 33%
• Empty base64 content or blank filenames will cause the node to error
• When converting File to Base64, the node handles files from any storage provider automatically
• Use expressions to build dynamic filenames from upstream data