How do I convert Hex back to a file?

Paste the Hex-encoded string into the input field. The tool will automatically decode it to binary data, processing each pair of hex digits (0-9, A-F) as one byte. Then, enter the filename with the correct file extension (e.g., "image.png", "document.pdf", "archive.zip") and click Download. The browser will save the decoded file to your downloads folder. The file will be byte-for-byte identical to the original file that was encoded. Make sure you paste the complete Hex string—since hex uses pairs of characters, missing even one character will result in a corrupted or incomplete file. Hex is case-insensitive, so "FF" and "ff" are equivalent.

Why do I need to specify a filename?

Hex encoding only preserves the binary data, not the filename or file type metadata. When you decode Hex to a file, you must manually specify the filename and extension because the decoder has no way to know what the original filename was. The file extension is crucial—it tells your operating system and applications what type of file it is and which program should open it. For example, use ".png" for images, ".pdf" for PDFs, ".zip" for archives, ".mp3" for audio, ".exe" for executables, etc. If you use the wrong extension, the file may not open correctly even though the data is intact. If you do not remember the original filename, use a descriptive name with the correct extension based on the file signature (first few hex bytes).

What happens if I use the wrong file extension?

Using the wrong file extension will not corrupt the data—the decoded bytes are still correct—but it may prevent applications from opening the file properly. For example, if you decode a PNG image but save it as "file.pdf", image viewers will not recognize it as an image, and PDF readers will fail to open it because the file signature (magic numbers) do not match a PDF. The solution is to rename the file with the correct extension. You can often identify the correct type by looking at the first few hex bytes: "89504E47" indicates PNG, "FFD8FF" indicates JPEG, "25504446" indicates PDF, "504B0304" indicates ZIP. Once you identify the type, rename the file with the proper extension and it will open correctly.

Can I decode Hex to get images back?

Yes! If you encoded an image (JPG, PNG, GIF, WebP, etc.) to Hex, you can decode it back to the original image file. Paste the Hex string, enter a filename with the correct image extension (e.g., "photo.jpg", "logo.png"), and download the file. The tool even shows a preview of the decoded image if you specify an image extension, so you can verify the image decoded correctly before downloading. The decoded image will be pixel-perfect identical to the original with the same resolution, quality, and file size. This works for all image formats including animated GIFs, transparent PNGs, and high-resolution photos. You can verify the image type by checking the first few hex bytes—PNG starts with "89504E47", JPEG starts with "FFD8FF".

Is my Hex string corrupted if decoding fails?

Decoding fails for several reasons: the Hex string contains invalid characters not in the set 0-9, A-F (remember hex is case-insensitive, so a-f works too); the string has an odd number of hex digits (hex requires pairs—2 digits per byte); the string is truncated or incomplete—missing even one hex digit corrupts the output; whitespace or formatting was not properly removed; or you are trying to decode something that is not actually Hex encoded. The tool will show an error message identifying invalid characters if present. If you copied the Hex string from somewhere, make sure you copied the entire string without truncation. Remove any "0x" prefixes, spaces, colons, or hyphens first. If the string is valid but produces a corrupted file, verify you are using the correct file extension.

How large can the Hex string be?

There is no hard limit on Hex string length, but browser memory limits apply. Hex strings representing small files (under 20 MB of hex text, about 10 MB original file size) decode instantly. Medium files (20-200 MB of hex text, about 10-100 MB original) work fine on most devices. Very large files (over 200 MB of hex text) may work but could cause browser slowdowns or out-of-memory errors, especially on mobile devices. Remember that Hex has 100% overhead—a hex string is exactly double the original file size because each byte requires 2 hex characters. For files over 500 MB original size (1 GB hex), consider using command-line tools instead of browser-based decoders.

Can I decode password-protected files from Hex?

Yes, but the password protection remains intact. If the original file was password-protected (like a password-protected ZIP or encrypted PDF), the Hex encoding preserves the encrypted binary data. When you decode the Hex string back to a file, you get the original encrypted file, and you will still need the password to open it. Hex encoding and decoding do not bypass, remove, or break encryption—they simply convert binary data to hexadecimal text and back. The file security and encryption are maintained throughout the process. After decoding, use the same password that was used to protect the original file to access the contents.

Why does my decoded file have a different size than expected?

The decoded file size should match the original file exactly. If it differs, several issues may have occurred: the Hex string was truncated or incomplete (missing hex digits at the end reduces file size); extra characters were added to the Hex string (increases file size and corrupts data); the Hex string has an odd number of characters (should always be even—2 per byte); spaces, prefixes, or separators were not properly removed before decoding; or the encoding was done incorrectly in the first place. Check that you copied the complete Hex string. Since each pair of hex digits represents one byte, you can calculate the expected file size: divide the hex string length by 2. Compare this to the original file size you expect.

Is my data safe when using this decoder?

Yes, completely safe! All Hex decoding happens entirely in your browser using JavaScript. The Hex string is never uploaded to any server, never transmitted over the internet, and processing happens purely on your device. Once you close or refresh the page, all data is immediately cleared from browser memory. This client-side approach ensures complete privacy—even the most sensitive files (financial documents, personal photos, encryption keys, proprietary data) can be safely decoded without leaving your device. However, remember that anyone with the Hex string can decode it to your original file just as easily, so keep hex-encoded sensitive data secure and never share hex strings of confidential files.

How do I identify the file type from Hex?

Look at the first 8-16 hex characters to identify the file signature (magic numbers). Common signatures: PNG images start with "89504E47"; JPEG images start with "FFD8FF" or "FFD8FFE0"; PDF documents start with "25504446" (hex for "%PDF"); ZIP archives start with "504B0304"; GIF images start with "47494638" (hex for "GIF8"); Windows EXE files start with "4D5A"; MP3 files often start with "494433" or "FFFB". Once you identify the signature, you can determine the correct file extension. If the first bytes do not match known signatures, the data might be raw binary, encrypted, or a less common format. Search online for "file signature database" or "magic numbers list" to identify unusual file types from their hex signatures.

Hex to File Decoder Online

Decode Hex (Hexadecimal/Base16) strings back to original files instantly. Convert hex to images, PDFs, documents, or any file type. 100% free, secure, and works in your browser.

File EncodeFile Decode

Hex string to decode

Output filename

Specify the filename with the correct extension (e.g., .png, .pdf, .zip)

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