Base64 Decoder

Base64 Decoder is a browser-based tool that converts Base64-encoded strings back into their original, human-readable text. Base64 is a widely used encoding scheme that represents binary or text data as a sequence of ASCII characters, making it safe to transmit over systems that handle only text — but the resulting output is intentionally unreadable without decoding it first. This tool removes that barrier instantly.

For developers, Base64 decoding is a routine but essential task. Whether you are inspecting token payloads, debugging API responses, unpacking configuration values, or reverse-engineering encoded data embedded in HTML or HTTP headers, having a reliable decoder at hand saves time and reduces the chance of manual errors. This tool handles standard Base64 as well as URL-safe Base64 variants, giving you accurate output regardless of the encoding flavor used.

Using the tool is straightforward: paste your Base64-encoded string into the input field and the decoded text appears immediately in the output area. There is no button to press — decoding happens in real time as you type or paste. The input should be a valid Base64 string, typically composed of alphanumeric characters along with +, /, and = padding characters. URL-safe Base64 uses - and _ instead of + and /, and this tool handles both formats automatically.

The output will be the original plain text that was encoded. If the source data was a JSON object, a JWT payload, an XML snippet, or a simple sentence, you will see it exactly as it was before encoding. Keep in mind that Base64 is an encoding scheme, not encryption — it provides no security, only a textual representation of data.

Edge cases to be aware of: if the input string is malformed or contains invalid characters, the tool will surface a clear error rather than producing garbage output. Strings with missing or incorrect padding (= signs at the end) may also fail to decode; if you suspect a padding issue, try appending one or two = characters to your input and decoding again. Binary data encoded in Base64, such as images or files, will not render meaningfully as plain text — for image data specifically, a dedicated image-from-Base64 tool is more appropriate.