Encode vs. Decode mode
The mode switch is the tool's main setting. Encode takes readable text and produces a Base64 string; Decode takes a Base64 string and restores the original text. Picking the wrong mode is the most common beginner error — if your output looks like more random characters instead of readable text, you probably encoded when you meant to decode.
A good habit: glance at your input before choosing. Readable words mean you want Encode; a long string of letters, numbers, plus signs, and slashes ending in = means you want Decode.
Character encoding: UTF-8
The tool treats your text as UTF-8, the web's standard character encoding. This matters because Base64 itself only understands bytes, and UTF-8 defines how characters become bytes. With UTF-8 handling, accented characters, CJK text, and emoji all encode and decode correctly.
Older tools sometimes assumed ASCII or Latin-1, which corrupts non-English text. If you have ever decoded Base64 and gotten mojibake — garbled characters like é instead of é — that was a charset mismatch. UTF-8 throughout avoids it.
Copy, clear, and swap controls
Next to the input and output boxes you will find the small utilities that make the tool pleasant to use: a copy button that grabs the result without selecting text manually, and a clear button that resets both boxes for the next value.
Use clear between batch items. Leftover text from the previous conversion is another classic source of confusion, especially when outputs look alike.
What the tool deliberately leaves out
You will not find file uploads, line-wrapping options, or URL-safe toggles here. That is intentional: the tool covers the core text-to-Base64 workflow that most people need, without settings that invite misconfiguration.
If you need the URL-safe variant (which replaces + and / with - and _), do that replacement in your own code after copying the standard output — it is a one-line change in any language.
When to leave every setting alone
Here is the honest truth about the settings: for the vast majority of conversions, the defaults are exactly right. Encode mode, UTF-8 handling, and the standard alphabet cover API keys, config values, data URIs, and debugging sessions. If you are unsure whether a setting needs changing, it almost certainly does not.
The only routine exception is the URL-safe variant, and even that is a post-processing step rather than a setting: encode normally, then swap the two characters in your own code. Resist the urge to overthink padding, line wrapping, or charsets unless a specific system demands it — simplicity is the configuration that prevents mistakes.
Frequently asked questions
Which mode should I choose?
Encode turns readable text into Base64; Decode turns Base64 back into readable text. Match the mode to your input: readable text means Encode, a Base64-looking string means Decode.
Why does the tool use UTF-8?
UTF-8 is the web standard and handles every language and emoji correctly. Older ASCII-only converters corrupt non-English text, so UTF-8 is the safe default.
Can I upload a file to encode?
No — the tool works with text you paste or type. For files, most operating systems have a built-in base64 command, or use a dedicated file encoder.
Is there a URL-safe Base64 option?
Not as a toggle. Copy the standard output and replace + with - and / with _ in your code; that is the entire difference.