123noteMake sense of that error.
Find the issue, review a suggested fix, and keep control of your original data.
Base64 Encode & Decode
FREEText, images, and files. Converted right here.
Processed on your device
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Ready when you are
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A little input. A useful result.Paste some text or try an example.
Your result will appear here.
Advanced options Padding · Validation · Line wrapping
Base64URL and padding are separate settings. Strict decoding does not remove spaces or line breaks.
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No account needed. Conversion stays on this device. Only text you choose to save is sent to your account. How this works ↗
Preparing offline shell…Saved text conversions
Checking your Google account…
Only text input and format options are sent when you press Save. Files, images and Data URLs stay on this device. Titles are readable account metadata; avoid sensitive titles.
Encoding isn’t encryption.
Base64 changes how data is represented. Anyone with the encoded value can decode it.
A quick guide to Base64 →Keep your workflow moving.
Text, files, and image Data URLs share one workspace. No extra tabs required.
A FEW QUICK ANSWERSLess guesswork.
Less guesswork.
More getting things done.
Why does my decoded result look like random characters?
The result might be a binary file, or text in a different character encoding. This version supports UTF-8 and lets you download the original decoded bytes.
Can this recover a truncated Base64 string?
No. Formatting changes can make some strings decodable, but cannot restore missing bytes. Copy the complete original value.
Does Base64 make a file smaller?
No. Padded Base64 uses 4 characters for each group of up to 3 input bytes, before line wrapping or a Data URL header.
A small tool for everyday debugging.
Choose what you have, choose a direction, and copy or download the result.
Choose your input
Use Text for a message or a Base64 string. File converts any file’s bytes. Image adds safe raster previews and embed formats.
Convert and inspect
Encode creates Base64. Decode turns Base64 back into bytes. UTF-8 text appears directly; binary results can be downloaded.
Take the result with you
Copy text, download a file, or use a text result as the next input. Only text conversions you explicitly save to your Google account are stored.
Standard or URL-safe?
Standard Base64 uses + and /. Base64URL uses - and _. Padding is configured separately. Select the format expected by the system you are working with.
When decoding fails
Read the error location. If the value contains line breaks, a Data URL header or missing padding, choose Review formatting fixes. Inspect the proposed changes, then apply them explicitly. Unknown characters and missing bytes are never silently repaired.
Images and files
PNG, JPEG, GIF and WebP signatures can be previewed after browser validation. Other file types are downloaded as bytes. HTML and SVG are never executed or rendered inline.
Working offline
Open this tool online once and wait for “Offline shell ready.” Offline conversion then uses cached app files. Browser storage can be cleared; installation does not guarantee that caches are retained.
Open converter →Your data stays out of the conversation.
Conversion happens in a browser worker. This tool has no analytics or advertising scripts. Only text you explicitly save is sent to account storage.
Local conversion
Your text and file contents stay in memory during processing. Downloading a result saves a file only when you choose to.
Storage is your choice
The app remembers format options and caches its shell. If you sign in and press Save conversion, the text and options are stored encrypted on the server. Files, images and Data URLs cannot be saved.
Understand the limits
The hosting provider receives normal page requests. Extensions, a compromised device or malicious page code can still access data. Local processing is not an absolute security guarantee.
Clipboard and downloaded files
Paste reads the clipboard only when you ask. Copy places the result on your system clipboard; other applications may access it. Downloaded data can contain harmful content. This tool does not scan files for malware.
Limits
Local conversion supports up to 5 MiB per task. Account storage is limited to 50 text conversions of up to 100 KiB each. Review the website Privacy Policy for retention and account details.