.mrpack vs .zip — What's the Difference?
Quick comparison
| .mrpack | Standard .zip | |
|---|---|---|
| Contains actual mod JARs? | ❌ No (URLs only) | ✅ Yes |
| File size | Tiny (KB) | Large (MB – GB) |
| Internet required to use? | ✅ Yes (to fetch mods) | ❌ No |
| Universally accepted by launchers? | ❌ No | ✅ Yes |
| Tied to a specific service? | Modrinth (manifest spec) | None |
| Includes config/scripts? | ✅ Yes (overrides) | ✅ Yes |
Why .mrpack is small and .zip is large
Because .mrpack stores only metadata (URL + hash + file size per mod), even a 200-mod pack can fit in 100 KB. A converted ZIP, on the other hand, contains every mod's actual JAR — typically hundreds of MB, sometimes over a GB.
Why simply renaming does not work
A .mrpack already is a ZIP under the hood. Renaming the extension lets you open it, but inside you only find the manifest and overrides — no mods. To get a usable modpack ZIP, the mods listed in the manifest must be downloaded and packed in. Our converter automates exactly that.