Base64 Encoder & Decoder – Image, PDF & File to Base64 / Data URI and Back

Convert any file to Base64 in bulk: images, PDFs, documents, audio or plain text. Get standard Base64, URL-safe base64url or a ready-to-paste data URI (data:image/png;base64,...). It also works the other way: decode Base64 or data URIs back into files or text, with the file type detected for you.

Built for automation: n8n, Make, Zapier and AI-agent workflows that need a data URI for an LLM vision API, an email attachment, a JSON payload or an HTML/CSS embed. $0.80 per 1,000 files, $0.20 per 1,000 texts. Failed and blocked inputs are free.

What it does

• Encode file URLs (direct links, Dropbox, Google Drive and GitHub share links are turned into direct downloads) and plain text (UTF-8).
• Three output formats: standard Base64 (optionally wrapped at 76 characters, MIME style), base64url (URL-safe, no padding) and data URI with the detected MIME type.
• MIME detection from the file content, not just the extension or server header: PNG, JPEG, WebP, AVIF, GIF, SVG, PDF, ZIP, MP3, MP4 and more.
• Optional image resize before encoding, e.g. max 1024 px, and re-encode as JPEG/PNG/WebP. This keeps LLM vision payloads and data URIs small. EXIF rotation is applied.
• Decode standard Base64, base64url (with or without padding) and data URIs (also percent-encoded data:,Hello%20World). Whitespace and line breaks are ignored. Text and JSON come back as text; images, PDFs and other binaries are saved as downloadable files with the correct extension.
• Large outputs are handled for you: outputs up to inlineMaxKb (default 256 KB) are returned in the dataset row; bigger ones are saved as a .txt record in the key-value store and the row gets a fileUrl.
• Every row has file name, MIME type, input and output size and a SHA-256 checksum.
• Safe and clear errors: web pages returned instead of files, HTTP errors, files over the size limit, private network addresses and social/video platform links (YouTube, TikTok, Instagram…, whose terms forbid downloading) each give a free error row. One bad input never stops the run.

Use cases

• Send images to OpenAI, Claude or Gemini vision APIs as data URIs from a no-code workflow.
• Embed logos and icons in HTML emails, CSS or JSON configs.
• Attach PDFs to APIs that only accept Base64 (invoicing, e-signature, email-sending APIs).
• Decode Base64 attachments from webhooks or API responses back into real files.
• Check a file's checksum and MIME type in bulk.

Input example

{
  "mode": "encode",
  "fileUrls": ["https://example.com/photo.jpg", "https://www.dropbox.com/scl/fi/abc/invoice.pdf?dl=0"],
  "outputFormat": "dataUri",
  "resizeMaxPx": 1024
}

Decode:

{ "mode": "decode", "base64Inputs": ["SGVsbG8sIEFwaWZ5IQ==", "data:application/pdf;base64,JVBERi0xLjQK..."] }

Output example

{
  "status": "ok", "type": "file", "input": "https://apify.com/img/apify-logo/logomark-32x32.svg",
  "fileName": "logomark-32x32.svg", "mimeType": "image/svg+xml", "inputSizeBytes": 688, "outputSizeBytes": 946,
  "sha256": "5c1f…", "outputFormat": "dataUri",
  "output": "data:image/svg+xml;base64,PHN2ZyB3aWR0aD0iMzIiIGhl…", "charged": true
}

A decoded binary file:

{ "status": "ok", "type": "decode", "mimeType": "application/pdf", "decodedSizeBytes": 15214,
  "fileName": "decoded-0003.pdf", "fileUrl": "https://api.apify.com/v2/key-value-stores/<id>/records/decoded-0003.pdf" }

The OUTPUT record summarises the run: files and texts converted, failures and megabytes processed.

Pricing (pay per event)

Event	Price
File converted (encode or decode, up to 10 MB)	$0.0008
Text converted (encode text, or decode to text)	$0.0002
Each further started 10 MB of a large file	$0.0015
Actor start	$0.00005

Errors, blocked URLs and skipped files are free. Set a maximum cost per run and the Actor stops cleanly at that limit.

Actor	Per file	Per text
This Actor	$0.0008	$0.0002
eliai/base64-encoder-decoder	$0.002	$0.001

Competitor prices are from the Apify Store on 2026-10-18.

FAQ

What is the size limit? 25 MB per file by default (maxFileSizeMb, up to 500 MB). Base64 output is about 33% larger than the file.

Why did my Google Drive link fail? The file must be shared as "Anyone with the link". Private links return a sign-in page, which the Actor reports as a free error.

Can I get the output without the data: prefix? Yes, choose base64 or base64url.

Is my data stored? Only in your own run's dataset and key-value store, which follow your Apify data retention settings.

Use with AI agents (Apify MCP)

This Actor works as a tool in the Apify MCP server. An agent can call it to turn an image URL into a data URI for a vision model, or to decode a Base64 attachment into a downloadable file.