Open GRP files in your browser
The file Duke Nukem 3D and the other Build engine games keep their levels, art and sounds in. Open one right here as a folder of its files. Nothing leaves your device.
Or drop it anywhere on this page
What you'll see
Your file opens like a folder, its files listed on the left, with a page beside them on what it is and what it holds.
- Listed like a folder • Unpacks only what you pick
- A page on what it is • From its own manifest or index
- Pictures, sounds and text • Each opens in its viewer
- Export • Save as ZIP or Extract all
About GRP
Ken Silverman's Build engine ran Duke Nukem 3D in 1996, then Shadow Warrior, Redneck Rampage and more, each with its data in one group file, like DUKE3D.GRP. The engine's code came out in 2000, and ports like EDuke32 still read GRPs, as do new games on the engine, like Ion Fury.
A GRP starts with KenSilverman, then its count of files, and for each a name of up to 12 letters and its size, then the files one after another. Inside are its levels (MAP), tiles (ART), sounds (VOC), music (MID), scripts (CON) and palette.
Filepeek lists every file, names the game when its files give it away and counts them by kind on the page. Sounds play, music plays through the MIDI player, scripts open as text, and Save as ZIP or Extract all take them out.
Build engine group file
.grp
Format
- MIME type
- application/octet-stream
- Made by
- Ken Silverman, for the Build engine
- Released
- 1996
Inside the file
- Starts with
- KenSilverman
- List
- A name of 12 letters and a size
- Then
- The files, one after another
- Holds
- MAP, ART, VOC, MID and CON
Opens in every browser
Filepeek opens a GRP as a folder in Chrome, Edge, Firefox and Safari. On their own, browsers only download it.
- YouChromeOpens through Filepeek
- YouEdgeOpens through Filepeek
- YouFirefoxOpens through Filepeek
- YouSafariOpens through Filepeek
Apps that open GRP
- WindowsEDuke32 • kextract, Ken Silverman's own
- MacEDuke32
- iPhone and iPadNo app opens it
- AndroidNo app opens it
Questions
How do I open a GRP file?
Drop it on this page or choose Peek a GRP. Its files are listed, and each one opens or saves on its own.
Can I see the levels?
Levels (MAP) and tiles (ART) are listed and save as they are, for the Build editor or a port like EDuke32. Sounds, music and scripts open here.
Can I take the files out?
Yes. Extract all writes them into a folder in Chrome and Edge, and Save as ZIP works everywhere.