Base64 Encoder / Decoder

Encode any text to Base64, or decode Base64 back to text. Supports standard and URL-safe variants.

Input URL-safe

Output

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Notes

Standard Base64 uses +, /, =. URL-safe replaces them with -, _ and drops padding.
Supports Unicode text via UTF-8 encoding.

About Base64 Encoder / Decoder

Base64 is an encoding that converts arbitrary binary data into a safe ASCII representation using a 64-character alphabet (A–Z, a–z, 0–9, plus + and /) with = padding. It is not compression: the output is roughly 33% larger than the original bytes, but it guarantees that data survives transport through text-only channels. This tool encodes text as UTF-8 and decodes Base64 back to the original string.

Reach for Base64 when you must embed or transmit binary data inside text-based protocols: email attachments, data URIs in HTML and CSS, or binary blobs in JSON fields. The URL-safe variant replaces + and / with - and _ and strips the = padding, so the output can appear safely in URLs, query strings, and filenames. Remember that Base64 is an encoding, not encryption — anyone can decode it, so never rely on it to protect secrets or passwords.

Encoding is not encryption

Base64 transforms bytes into a 65-character alphabet so they survive transports that only handle text. It is reversible by design: anyone who can decode the output can read exactly what you encoded. Treating Base64 output as if it were a secret is the most common mistake with this tool.

Use it for embedding binary in JSON, putting a small binary blob in a URL-safe string, or representing data that must survive a text-only channel. Do not use it to hide credentials.

URL-safe variant

Standard Base64 uses `+` and `/`, both of which need percent-encoding in a URL or a filename. The URL-safe variant substitutes `-` and `_` and drops the padding `=` characters. JWTs, many cookie formats and most URL-embedded payloads use this variant.

When decoding output from elsewhere, try the standard alphabet first and switch on failure — that ordering avoids subtle corruption when a payload happens not to contain `+` or `/`.

Limits

Encoding expands the data by about a third: three bytes become four characters. For binary data this is unavoidable in a text channel, but it means Base64 is the wrong choice for large payloads where the transport already handles binary.

Next steps

Base64 Image Viewer— view images encoded in base64

Frequently Asked Questions

How do I encode text to Base64?

Paste your text into the input and click Encode. The tool converts it to Base64 using UTF-8 encoding. Click Decode to reverse the process and convert Base64 back to plain text.

Is the encoding done locally?

Yes. All encoding and decoding uses the browser's built-in TextEncoder and TextDecoder APIs. No data is transmitted to any server.

Is my data sent to a server?

No. Every tool on jsonversal runs entirely in your browser using the Web Crypto API, File API, and Clipboard API. Nothing is ever uploaded — not even the JSON you paste in.

Do I need an account or API key?

No signup, no email, no API key. All tools are free to use with no signup required.

Can I use these tools offline?

Yes. Once the page loads, all tools work offline. There are no external API calls or CDN dependencies at runtime.

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Your data never leaves your device

All processing happens in your browser. No uploads, no tracking, no servers. Your API keys, configs, and private payloads stay private — 100% client-side.