How it works
Choose Text or File mode
Paste text/Base64 directly, or switch to File mode to upload an image, PDF, or any file.
Encode or decode instantly
Click Encode/Decode for text, or the file processes automatically on upload — all in your browser.
Optional URL-safe format
Toggle URL-safe Base64 for use in URLs, filenames, or JWT tokens without extra escaping.
Copy the result
Copy the raw Base64 string, or the full data: URI ready to paste into HTML/CSS.
Base64 encoding and decoding in code
Need to encode or decode Base64 programmatically — for API auth headers, data URLs, or file transfers? Here's the correct way in each language:
What is the Base64 Encoder / Decoder and how does it work?
This base64 encoder / decoder lets you encode and decode text using Base64 encoding for APIs, tokens, data URIs and configuration files — entirely in your browser with no uploads, no sign-ups, and no waiting. Enter your data, adjust any settings, and get instant results that you can copy or download with one click.
Whether you use this tool once for a quick task or rely on it daily as part of your workflow, it remains completely free with no usage limits, no account requirements, and no advertisements interrupting the experience. Everything runs locally using JavaScript — your data never touches a server, which matters especially when you are working with personal photos, sensitive text, or private information of any kind.
Why a browser-based base64 encoder / decoder matters
Many competing tools require you to upload data to their servers for processing, which introduces privacy concerns, upload waiting times on slow connections, and dependency on the service staying online. This tool eliminates all three problems: processing happens on your own device using your browser's built-in capabilities, results appear instantly regardless of your internet speed, and the tool works even offline once the page has loaded. For anyone working with content that shouldn't be shared with third parties — personal photos, client data, business documents — this local-processing approach is a genuine advantage rather than just a marketing claim.
Common use cases for the base64 encoder / decoder
This tool serves a wide range of practical everyday needs: content creators preparing assets for social media platforms, students working on assignments and presentations, developers handling data transformations during coding, small business owners managing their online presence without expensive software subscriptions, and professionals across dozens of fields who simply need a quick, reliable utility without the overhead of installing desktop software or creating accounts on yet another platform. The tool does one job, does it well, and gets out of your way.
Tips for getting the best results
Start with the highest quality input you have available — better input produces better output regardless of the tool. Use the specific options and settings the tool provides rather than accepting defaults, since they exist to let you fine-tune the result for your particular use case. If you use this tool regularly, bookmark it for instant access rather than searching for it each time — the page loads in under a second and begins working immediately. For sharing with colleagues or team members, simply share the page URL — no accounts or installations needed on their end either.
Base64 for files and images — not just text
Beyond plain text, this tool also encodes entire files — images, PDFs, fonts, or any binary file — directly in File mode. Upload a file and the tool instantly generates a complete data: URI (like data:image/png;base64,iVBORw0KG...) with the correct MIME type detected automatically, ready to paste straight into an HTML <img> tag or a CSS background-image property. This is the standard technique developers use to embed small icons and images directly into a stylesheet or email template without a separate image request.
Standard vs. URL-safe Base64 — which one do you need?
Standard Base64 uses + and / as two of its 64 characters, both of which have special meaning inside URLs and file paths. URL-safe Base64 (RFC 4648) swaps these for - and _ instead, so the encoded string can be dropped directly into a URL query parameter or filename without extra escaping. JWTs (JSON Web Tokens) and most modern REST APIs use the URL-safe variant by default — toggle the checkbox above if your target system expects it.
- 1Mistaking Base64 for security. It's an encoding, not encryption — anyone with the string can decode it in one line of code. Encrypt first if the data is sensitive.
- 2Forgetting the size overhead. Base64 output is always about 33% larger than the source — factor this in when embedding files inline versus linking to them.
- 3Using standard Base64 in a URL. The + and / characters can break query strings — switch to URL-safe encoding for anything going into a URL.
- 4Missing padding on decode. A valid Base64 string's length should be a multiple of 4; this tool automatically restores missing = padding before decoding.
| Character | Standard Base64 | URL-safe Base64 |
|---|---|---|
| 62nd value | + | - |
| 63rd value | / | _ |
| Padding | = required | Often omitted |
| Safe in URLs? | No | Yes |
Standard vs. URL-safe Base64 character differences
💡 Key takeaways
- Free base64 encoder / decoder — instant results entirely in your browser
- No sign-up, no upload, 100% private processing on your device
- Works on every device — phone, tablet, desktop, any operating system
- No usage limits — use it as many times as you need, forever free
Pro tip: Bookmark this base64 encoder / decoder for instant access — it loads in under a second, works offline once cached, and saves you from searching for it every time you need it.
Why choose our tool?
100% Private
Everything runs in your browser. Your data never leaves your device — no uploads, no server processing, no tracking.
Instant Results
No loading screens, no waiting, no queues. Results appear the moment you click — powered by client-side JavaScript.
No Sign-Up Ever
No accounts, no emails, no passwords. Just open the page and start using it — forever free, no strings attached.
Works Everywhere
Phone, tablet, laptop, desktop — any browser, any OS. Fully responsive and works offline once loaded.
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