Base64 Decoder
Decode Base64 strings back to plain text instantly.
What is Base64 Decoding?
Base64is an encoding scheme that represents binary data as plain ASCII text, using 64 characters (A–Z, a–z, 0–9, +, /). It's used wherever binary or non-ASCII data needs to travel safely through a text-only channel — email attachments, JWT tokens, API payloads, environment variables, and data: URIs embedded in HTML or CSS all commonly carry Base64-encoded content.
Decoding reverses that process: it takes a Base64 string and converts it back to its original form. This tool decodes Base64 back to readable plain text, which works for anything that was originally text (JSON, JWT segments, config values, plain messages). Binary data such as images would decode to raw bytes rather than readable text.
It's important to remember that Base64 is not encryption — it provides no confidentiality. Anyone can decode a Base64 string without a key, so it should never be relied on to protect sensitive information.
This page lets you decode Base64 online for free, directly in your browser. Paste any Base64 string and get the original text back instantly — nothing is uploaded or sent to a server.
Why Decode Base64?
API & JWT Payloads
Tokens, API keys, and JWT segments are frequently Base64-encoded — decoding them reveals the underlying JSON or raw value for debugging.
Email Attachments
Raw email source (MIME) encodes attachments and non-ASCII content in Base64. Decoding a segment lets you inspect what was actually sent.
Config & Secrets
Environment variables and Kubernetes Secrets often store values Base64-encoded. Decoding confirms exactly what a deployed config contains.
Data URIs
Images and fonts embedded directly in HTML/CSS via data: URIs are Base64-encoded — decoding helps verify or extract the original asset.
Example
Here's a Base64 string and the plain text it decodes to.
SGVsbG8sIFdvcmxkIQ==Hello, World!Features
Decode Instantly
Paste a Base64 string and get the original plain text back immediately.
100% Client-Side
Decoding happens entirely in your browser. Your data is never uploaded or sent to a server.
Email & MIME
Decode Base64 payloads pulled from raw email source or MIME attachments.
Data URIs
Decode the Base64 portion of a data: URI to inspect the underlying encoded content.