Local processing
Originals, patches and results stay in your browser. Their contents are not uploaded to a server.
Browser-based xdelta patcher
Apply an xDelta patch online
Choose the original file required by your patch and an .xdelta file. Patching runs in your browser, without uploading your files.
Patch a file
Local file processingYour original. Your patched result.
What is xDelta Patcher?
This browser tool applies the changes in an .xdelta patch to its matching original file. It creates a separate result for you to download, leaving your original unchanged.
A translation, ROM hack or update may need a particular region or revision. Start with the exact file named by the patch creator. Learn what an xDelta patch contains.
Two files in. One result out.
The original supplies existing data.
The patch tells the tool what to change.
Getting started
How to apply an xDelta patch
- 01
Match your files
Check the creator’s instructions, then select the required original and its xDelta patch.
- 02
Apply the changes
Check the output name, apply the patch and keep this tab open while it runs.
- 03
Save the result
Find the new file in your browser’s downloads. Use Download file if you need to try again.
Built around your files
Features of xDelta Patcher
Useful controls, right where you need them.
Any original extension
Select the file your patch needs, including unfamiliar names. The patch input stays specific to xDelta.
Files inside archives
A single suitable entry is extracted automatically. Choose the correct file when an archive contains several.
A name you can change
The patch name suggests an output filename. Edit the name or extension to match the creator’s instructions.
Checksum handling
Validation stays on by default. Clear errors help you check the source before considering a checksum bypass.
A separate download
Apply patches in your browser without installing this tool. Keep the result button available until your file is saved.
Supported original files
Start with the file your patch expects.
The original can be a ROM, disc image, another file type or a file without an extension. Changing its name does not change its contents or make it compatible.
Choose .xdelta for the patch, or a ZIP containing one. Other patch formats need a different tool.
.gb.gbc.gba.nds.nes.isoother files
512 MiB output / extracted-file limit. Browser memory can impose a lower limit, especially on phones. Accepting a filename does not guarantee every patch or file size will work.
Guides & articles
Get the right result.
How to use xDelta Patcher
Select your original and patch, choose ZIP entries and save the output.
Read the guide
Fix an xDelta checksum mismatch
Check source versions, file hashes and ZIP selections when validation fails.
Read the guide
What is an xDelta file?
Understand how a patch and its matching original produce a new file.
Explore the articleHow do I know which original file to use?
Follow the patch creator’s required region, revision and file format. Some patches need an unmodified original; an update may need a previously patched version. Compare a source hash if the creator provides one. A similar filename is not enough.
Can I choose a ZIP instead of extracting it first?
Yes. A single suitable source file or .xdelta patch is extracted automatically. If several files remain, choose the right entry. Common archive metadata is ignored; a lone README or license needs an explicit choice. Use Choose a different file inside to reopen an original ZIP, or Use ZIP file itself only if the patch expects the archive’s raw bytes.
Why am I getting a checksum mismatch?
The result did not match the checksum stored in the patch. Check the required original and the patch download before bypassing validation. Renaming the source will not fix a mismatch. Work through the source checks.
Where does the patched file go?
Your browser controls the save location. Check its download list or chosen folder. If the automatic download did not start, use Download file. Keep the tab open until the result is saved.
Can I patch a file larger than 512 MiB?
The tool limits patched output and each extracted ZIP entry to 512 MiB. An original with a larger size can be selected directly, but that does not guarantee decoding will fit in memory. For a target above the limit, use a desktop xdelta patcher.
Are my files uploaded or stored by the website?
No file contents, filenames or hashes are uploaded by the patcher. Selected files and the result stay available in the current page until you clear or replace them, or leave. Website analytics are separate; see the Privacy Policy.
Does a successful patch mean the game will run?
It means processing finished. Check any expected output hash and follow the creator’s instructions for the result and emulator. A successful decode, especially with validation bypassed, is not a universal compatibility check.