Base64 Encoder & Decoder

Base64 encoding converts arbitrary binary data — or any string — into a subset of printable ASCII characters. It is used in HTTP Basic Authentication headers, data URIs for inline images, JWT payloads, and environment variable values when the raw value contains characters that would break shell parsing or YAML formatting.

Common uses

API credentials: many services encode client_id:client_secret in Base64 and send it as an Authorization: Basic ... header. Data URIs: images and fonts can be embedded directly in CSS or HTML as data:image/png;base64,.... Config values: TLS certificates, SSH keys, and JSON blobs are often Base64-encoded before storage in environment variables or Kubernetes secrets.

Base64 is not encryption

Base64 is an encoding, not encryption. Anyone who receives a Base64 string can decode it instantly — including with this tool. Never use Base64 to "protect" sensitive data. Use it only as a transport encoding for data that is already secured or that does not need to be secured.

This tool handles Unicode correctly by using encodeURIComponent + btoa for encoding and the reverse for decoding, preventing the common "string contains characters outside Latin1" error that plain btoa throws with multi-byte characters.