StackedThink

Blog

AI Audiobook Automation for Digital Creators

05 April 2025

Convert any text-based ebook or guide into a professional audiobook using Zapier automation and AI voice synthesis APIs.

Who This Is For

You're a digital product creator with existing guides, ebooks, or lead magnets sitting idle in text format. You know content repurposing works — but manually converting each piece into audio is time-consuming.

This automation recipe lets you turn any text-based digital asset into a professional-sounding audiobook without lifting a finger, using AI voice synthesis APIs like ElevenLabs or Amazon Polly.

The Outcome

With this automation:

  • Upload a text file (e.g., a blog post, guide, or planner) to Google Drive or Dropbox.
  • Zapier detects the file and converts it into an audio file using AI voice synthesis.
  • The final MP3 is uploaded back to your cloud storage, ready for use on Gumroad, Teachable, or embedded on your site.

This unlocks new revenue streams by repurposing existing content into multiple formats, as explored in our AI Prompt Pack for Indie Makers.

Automation Flow

Trigger

New File in Folder (Google Drive or Dropbox) — Watches a designated folder for new .txt, .md, or .docx files.

Steps

  1. Extract Text Content — Use a parser (like Docx2txt or Plaintext Extractor) to get clean text from the uploaded file.
  2. Chunk Text — Split the text into digestible chunks (e.g., 3000-character segments) to comply with API limits.
  3. Generate Audio — For each chunk, call an AI voice synthesis API (ElevenLabs, Amazon Polly, etc.) to generate an audio file.
  4. Merge Audio Files — Combine all audio chunks into a single MP3 using an audio merging tool (like FFmpeg via cloud function or third-party API).
  5. Upload Final Audiobook — Save the final MP3 to a specified folder or cloud storage bucket.

Final Output

A fully automated audiobook creation pipeline that turns any written content into a downloadable MP3, ready for monetisation.

Importable Recipe (Zapier JSON)

{
  "zap": {
    "trigger": {
      "type": "google_drive_new_file_in_folder",
      "folder_id": "YOUR_FOLDER_ID",
      "file_types": ["txt", "md", "docx"]
    },
    "actions": [
      {
        "type": "util_text_extractor",
        "input": "{{file_content}}"
      },
      {
        "type": "util_text_chunker",
        "chunk_size": 3000
      },
      {
        "type": "api_call",
        "service": "elevenlabs",
        "endpoint": "/text-to-speech",
        "method": "POST",
        "payload": {
          "text": "{{chunk}}",
          "voice_id": "YOUR_VOICE_ID"
        },
        "output": "audio_chunk_{{index}}.mp3"
      },
      {
        "type": "util_audio_merger",
        "files": ["audio_chunk_*.mp3"],
        "output": "final_audiobook.mp3"
      },
      {
        "type": "google_drive_upload_file",
        "folder_id": "OUTPUT_FOLDER_ID",
        "file_name": "{{original_filename}}_audiobook.mp3"
      }
    ]
  }
}

Step-by-Step Setup Guide

  1. Create a Folder for Input Files

    • In Google Drive or Dropbox, create a folder called Audiobook Input.

  2. Set Up the Trigger

    • In Zapier, choose "New File in Folder" and connect your storage account.
    • Select the Audiobook Input folder.

  3. Add Text Extraction Step

    • Use a utility action to extract clean text from .txt, .md, or .docx files.

  4. Chunk the Text

    • Use a text chunker utility to split content into API-compatible sizes (e.g., 3000 characters).

  5. Generate Audio Chunks

    • Connect to ElevenLabs or Amazon Polly API.
    • Configure the API to generate audio for each chunk.

  6. Merge Audio Files

    • Use a tool like FFmpeg via a cloud function or API to merge all audio files.

  7. Upload Final Audiobook

    • Save the final MP3 to a new folder or send it directly to Gumroad or a podcast host.

Troubleshooting FAQ

Q: What if my text is too long?

A: The chunking step handles this automatically. Each chunk is sent separately to the voice API, and the final audio is merged.

Q: Can I customise the voice?

A: Yes — ElevenLabs and Polly allow you to select voice IDs and even clone custom voices.

Q: What file formats are supported?

A: Currently .txt, .md, and .docx. You can add more by extending the parser step.

Q: Can I use this with Notion or Airtable?

A: Yes — just swap the trigger to a new record or page in those apps and extract the text content.

Monetisation Next Step

Want to automate more digital product workflows like this one?

Check out our Content Strategy Calculator to estimate ROI on content repurposing, or explore our AI Prompt Pack for Indie Makers to supercharge your automation game.

Or spin up your own repurposing tool using our Automation Recipes Hub.

← Back to blog