Why JSON uses base64
JSON strings cannot safely hold raw binary. APIs base64-encode PDFs, images, and certificates into string fields like "content" or "data".
Watch for double encoding: sometimes the JSON itself is fine but the inner value is a data URI or URL-safe base64 variant.
Decoding workflow
Extract the string field, paste into base64app, enable auto-repair, and decode. Use /base64-to-json/ when the payload is UTF-8 JSON text.