Convert JPG / JPEG to Base64
Drop a JPG or JPEG image to get its Base64 string and Data URI, with an instant preview, dimensions and file size — all in your browser.
Input — JPEG file○ Waiting for input
Drag & drop a JPEG here
or
Inspection Report
File metadata
- Detected Type
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- MIME Type
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- Encoding
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- Input Length
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- Decoded Size
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- Padding Status
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- Data URI
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- File Signature
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- Preview Availability
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How to convert JPG / JPEG to Base64
To convert a JPG to Base64, drag and drop the image onto the tool above or choose it from your device. The tool verifies the JPEG format, shows a preview with dimensions and file size, and gives you the Base64 string, a data:image/jpeg;base64,... Data URI, and ready-to-use HTML and CSS snippets — without uploading anything.
How to Use
- Drag a .jpg or .jpeg file onto the drop zone, or click Choose File.
- The tool validates the JPEG signature and shows a preview with exact dimensions and file size.
- Copy the plain Base64 or the Data URI, depending on where you will use it.
- Grab the HTML <img> snippet or CSS background snippet if you are embedding the image.
- To go the other way, use the Base64 to JPG tool.
Real Example
A 1920 × 1080 photo of 245 KB encodes to a Base64 string of about 327,000 characters, starting with /9j/ — the signature every Base64 JPEG shares, because every JPEG file begins with the bytes FF D8 FF. The inspector confirms Detected Type: JPEG, MIME: image/jpeg before you copy anything, and the preview shows the exact dimensions (1920 × 1080) and file size, so a wrong file never makes it into your markup.
Code Snippets
// Encode a JPG as a Data URI (browser)
const dataUri = await new Promise(resolve => {
const reader = new FileReader();
reader.onload = () => resolve(reader.result);
reader.readAsDataURL(file); // "data:image/jpeg;base64,/9j/..."
});How JPG to Base64 Works
JPEG files always open with the three bytes FF D8 FF, which is why their Base64 form reliably starts with /9j/. This tool checks those bytes before encoding, so a PNG renamed to .jpg is caught instead of silently mislabeled. The Data URI output combines the encoded data with the image/jpeg MIME label in the standard data: format that HTML and CSS understand. Encoding is a byte-for-byte, lossless representation of the file — the image is never recompressed, resized or otherwise modified.
Common Use Cases
- Inlining a small photo or logo directly into an HTML email or page.
- Embedding a JPEG in a CSS file as a background image.
- Attaching an image to a JSON API request as a Base64 field.
- Storing a thumbnail in local storage or a text-only database column.
FAQ
Does this tool support both .jpg and .jpeg files?
Yes. Both extensions are the same JPEG format, and the tool checks the actual file bytes rather than the extension, so either one works.
What Data URI prefix does a JPEG image use?
A JPEG Data URI starts with data:image/jpeg;base64, followed by the encoded data. The Data URI output tab adds this prefix for you automatically.
How do I embed the Base64 output in an HTML img tag?
Use the HTML snippet tab: it produces <img src="data:image/jpeg;base64,..."> with your data already inside. Paste it anywhere an img tag is valid.
Will converting to Base64 change my image quality?
No. Base64 is a lossless, byte-for-byte encoding of the file. The image is not recompressed, so the decoded result is identical to the original.
Why was my file rejected?
The file's bytes did not match the JPEG signature — it is probably a different format saved with a .jpg name. Convert it with the tool that matches its real format, such as PNG to Base64, or the multi-format Image to Base64 tool.