diffpatchtool.com · by Reproteq · Author: Alex G.T.
DiffPatchTool is a desktop application for comparing, generating diffs, applying patches, inspecting, and editing binary files — designed especially for working with ECU firmware (.bin), but suitable for any pair of binary files.
Written in Rust, it compiles to a single portable .exe with no external dependencies. It features a modern light theme, embedded icons, a colored hex viewer, an optional online patch catalog, and automatic updates from GitHub.
- Features
- Diff Format
- Usage
- Online Patch Catalog
- Account & Plans
- Server Connection
- Settings and System
- Updates
- Building
- In Development / Future
- Support My Work
- Contact
- License
- Byte-by-byte comparison of two files using a list of differences.
- 3-column diff format (
address,old value,new value), with backward compatibility for older 2-column patches. Patches are saved as_patch.diff; older.txtpatches are also supported. - Patch application with original-value verification and a warning if the base file does not match.
- Hex comparator with an editor-style interface: two side-by-side A | B panels, changed bytes highlighted in red, offsets in blue, and an ASCII column.
- Configurable dump view: 8 / 16 / 32-bit, endianness (lo-hi / hi-lo), and base (hex / decimal) — inspired by WinOLS.
- Advanced selection: consecutive, rectangular, and row-based selection; define a block using start/end offsets; select/deselect all.
- Selection operations: fill with
00/FF,XOR, or write a typed value across the entire block. - Copy and paste bytes (Ctrl+C / Ctrl+V), preserving the rectangular shape when pasting.
- Undo / redo (Ctrl+Z / Ctrl+Y), including byte-by-byte editing.
- Context menu with copy, paste, fill, define block from byte, copy selection to a new file, and write to clipboard.
- Hex and ASCII search in A or B, with match highlighting.
- Navigation between differences and jump to a specific offset (
Goto). - Analyzer: extracts ECU identifiers automatically.
- Online patch catalog: search a public, community-driven catalog and download compatible patches — no full firmware ever leaves your machine.
- Cloud sync (optional): save your patches online and access them from any machine with a Pro or Premium account.
- Persistent configuration (
config.json): remembers view preferences, selections, and options. - Progress bar for large operations using background processing, keeping the interface responsive.
- Automatic updates from GitHub Releases, including automatic restart after installation.
- Byte-by-byte comparison of two files using a list of differences.
Saving a diff produces three columns:
0xADDR 0xOLD 0xNEW
- ADDR — offset (address) of the changed byte
- OLD — old value (byte from file A / original)
- NEW — new value (byte from file B / modified)
Patches are saved as:
<B>_<timestamp>_patch.diff
Older .txt patches using either the 2-column or 3-column format are still supported.
Drag and drop files onto A (original) and B (modified or a .diff file), or click each area to select them. Files can also be loaded from the Functions menu.
Compare A and B and save the differences to:
<B>_<timestamp>_patch.diff
The diff uses the 3-column format. The application displays the name, size, and date of each file, along with the number of differences found.
Load the original file into A and a .diff file (or an older .txt patch) into B to generate a patched file.
If the patch contains the original values, DiffPatchTool verifies that they match the values in A and displays a warning if the base file is not the correct one.
Opens a separate window displaying the hexadecimal dump of A and B side by side.
- Offsets in blue, changed bytes in red, and edited bytes in orange.
- "Differences only" mode with context lines, or full binary mode.
- Configurable view: 8 / 16 / 32-bit, endianness (lo-hi / hi-lo), and base (hex / decimal).
- Toolbar organized by function: navigation, location, selection/editing, and view controls.
- Can open a single file in editor mode in addition to comparing two files.
- Click a byte to select it and type 2 hexadecimal digits to change it; the cursor automatically advances to the next byte.
- Selection modes: consecutive, rectangular (only the columns within the rectangle), or row-based.
- Define block by entering the start and end offsets, or directly from the context menu on a byte.
- Operations on the selection:
00,FF,XOR, or enter a value to apply it to the entire block. - Copy / paste bytes (Ctrl+C / Ctrl+V); rectangular selections preserve their shape when pasted.
- Undo / redo (Ctrl+Z / Ctrl+Y).
- Copy selection to a new file (
.bin). - Save edited A and/or B as new
.binfiles, or export the diff of the current state including all edits.
- Goto: enter an offset in hexadecimal and jump directly to it, centered in the view.
- Find: search in Hex (
C2 FC 01) or ASCII text, in either A or B, with highlighting and next/previous navigation. - Difference arrows: navigate through differences one by one, automatically centering each.
When a file is loaded, the Analyzer automatically extracts relevant identifiers such as Bosch part numbers, EDC17 / MED17 / MD1 versions, and other ECU-related information. It can be enabled or disabled from Settings.
DiffPatchTool connects to a public patch catalog at diffpatchtool.com/catalog — browsable by anyone, no account required.
- Search by vehicle, ECU, hardware/software version, or signature. When a file is loaded, the app can find patches that match it using address/value fingerprints — your full firmware is never uploaded.
- Verify before applying. Each candidate carries its start/end signatures, so the app checks that the expected original bytes are present in your file before you patch anything.
- Community ratings. Patches can be rated 1–5 stars, so you can see what actually works.
- Public or private. Mark each patch public to share it with the community, or keep it private for yourself.
- No duplicates. Every upload is checked by a content hash, so the public catalog stays clean.
Logging in is optional — all local features work without an account or Internet connection. An account adds cloud features on top.
Uploads and downloads share a single daily allowance, on both the desktop app and the website. Downloading your own patches is always free.
| Plan | Daily limit | Price |
|---|---|---|
| Free | 10 / day | 0€ |
| Pro | 30 / day | 9.99€/mo |
| Premium | 100 / day | 29.90€/mo |
- Cloud-saved patches and synced searches across every machine you use.
- Device management: your account can be linked to a limited number of machines, managed from the web portal.
See full details at diffpatchtool.com/pricing.
DiffPatchTool can optionally connect to the server at diffpatchtool.com for online features.
Logging in is not required to use the application — all local features remain available without an account or Internet connection.
- Connection icon in the toolbar: gray when disconnected, green when connected. Clicking it opens the login dialog or logs out.
- Optional login using a diffpatchtool.com account. The session can be remembered between launches using a token.
- Connecting enables saving and sharing patches, searching the catalog against the currently loaded file, and checking whether a patch matches it.
- Settings configure app preferences (view, analyzer, and more).
- System menu displays system information:
- Machine identifier (HWID)
- Operating system
- CPU
- RAM
- Executable path
- Application version
DiffPatchTool checks for a new version on GitHub at startup and through the toolbar update button.
If a newer release is available, a button lets you download and install the update. The executable is replaced and the application automatically restarts after installation.
DiffPatchTool.exe is compiled and ready to use — just download it. 🎉
DiffPatchTool is under active development. Upcoming work includes:
- Smarter catalog matching: rank compatible patches by fingerprint confidence and ECU identifiers.
- Patch marketplace: optional paid patches, with ratings and download stats.
- More hex viewer modes: float, signed, and binary representations.
- Offline license hardening for cloud features.
- Continuous performance and usability improvements.
If you find this project useful and would like to support its development, any amount is welcome and greatly appreciated!
PayPal: reproteq@gmail.com
Quick donate: €1 · €5 · €10 · €25 · €50 · €100 · Any amount
Bitcoin (BTC):
1Mmwhdw4mQzbuLbmPFdEF2uXMVi8X3kv68
- Website: diffpatchtool.com · reproteq.com
- Email: reproteq@gmail.com
- Telegram: @reproteq
- Ali-G ❤️ — For your incredible contribution and support! 🎉
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