Base64 to JavaScript Converter: Decode Base64 Online
The Base64 to JavaScript converter decodes raw Base64, Base64URL, and data:text/javascript;base64,... URIs into JavaScript, removing the data URI prefix automatically. It accepts whitespace and missing padding. You can optionally auto-beautify the decoded result and check whether it parses as valid JavaScript; invalid JavaScript produces a non-blocking warning rather than stopping the conversion.
Base64 to JavaScript is a browser-based converter for turning encoded JavaScript content into JavaScript you can inspect and copy. It accepts raw Base64, Base64URL, and data:text/javascript;base64,... URIs, and automatically strips the data URI prefix. Use it when you need to decode content without manually handling the encoded string.
The conversion accepts whitespace and missing Base64 padding, which can make pasted input easier to work with. After decoding, you can optionally auto-beautify the JavaScript. The tool also checks whether the result parses as valid JavaScript; if it does not, it displays a non-blocking warning rather than preventing the conversion.
Base64 represents data as text, while JavaScript is a programming language used to write code. Base64URL is a URL-safe variant of Base64, and a data URI can include a media type and encoding information before the encoded content. Converting these inputs to JavaScript is useful when you want to inspect, reuse, or share the decoded content in a form that is easier to read.
The Base64 to JavaScript converter runs entirely in your browser: your input is processed on your device and is not uploaded, stored, or sent to a server. It works offline once the page has loaded. Developers and DevOps engineers can use it to examine encoded snippets, prepare content for another system, or check a conversion before using the result.
Step 1: Paste your raw Base64, Base64URL, or data:text/javascript;base64,... input. The converter strips the data URI prefix automatically.
Step 2: Choose whether to auto-beautify the decoded JavaScript. Beautifying is optional, so you can leave the result unformatted if you prefer.
Step 3: Run the conversion to decode the input. Whitespace and missing Base64 padding are accepted.
Step 4: Review the JavaScript result and any validation warning. A warning appears if the decoded content does not parse as valid JavaScript, but it does not block the conversion.
Step 5: Copy the result for your code, documentation, ticket, or other destination.
Use case: Move encoded JavaScript into a system that only accepts JavaScript. Decode the Base64 content first so it is easier to use in that context.
Use case: Check whether JavaScript content you received matches its Base64 representation. Decoding lets you inspect the resulting code directly.
Use case: Prepare decoded JavaScript snippets for documentation, a ticket, or a commit message. Optional auto-beautifying can make the result easier to read.
Use case: Sanity-check a conversion before pasting the result into code. The JavaScript parsing check can show a non-blocking warning if the result is invalid.
Use case: Inspect a JavaScript data URI without manually removing its prefix. Paste the URI and let the converter strip the prefix automatically.
Use case: Work with Base64URL-encoded JavaScript when you need the decoded content in JavaScript form. The converter accepts Base64URL as well as standard Base64.