XML vs binary plist

The same property list can be stored as human-readable XML or compact binary. The data is identical — only the serialization differs. Drop a file below to see it as XML and convert it back.

Same data, two encodings
Convert both ways
Types and key order preserved
Nothing uploaded

Ready to open a file processed locally — nothing is uploaded

Two serializations of the same thing

Apple's Property List Programming Guide defines the property list as an abstract object graph — dictionaries, arrays, strings, numbers, booleans, dates and data — that can be serialized in more than one way. NSPropertyListSerialization names the two modern formats xml1 and binary1. Whichever one a file uses, reading it produces exactly the same object graph.

XML plist (xml1)

Starts with <?xml and declares Apple's PropertyList-1.0.dtd.
Readable and editable in any text editor; diffs cleanly in git.
Used for files developers maintain by hand: Info.plist in source control, .entitlements, most OpenCore config.plist setups.
Larger on disk — every value carries markup around it.

Binary plist (binary1 / bplist00)

Starts with the magic bytes bplist00, followed by an object table and a trailer.
Smaller and much faster to parse — no text scanning.
macOS writes user defaults (~/Library/Preferences), many system caches and most .mobileprovision profiles in binary.
Unreadable in a text editor — you must convert it first.

How to convert between them

On a Mac, Apple's own tool is plutil: plutil -convert xml1 file.plist turns binary into XML, plutil -convert binary1 file.plist goes the other way, and Xcode converts Info.plist files automatically when building.

Without a Mac, use the editor above: it detects the format on open, always shows the file as XML, and Download saves it as either xml1 or binary1. Conversion is lossless — types (integer vs real, dates, data) and dictionary key order are preserved exactly, so a round trip produces a file Apple's tools accept.

Which should you choose?

Keep XML in source control — it diffs and reviews well. Let binary stay where the system put it — preferences and profiles are rewritten by macOS anyway, and parsing speed matters there. When you need to inspect a binary file, convert a copy to XML rather than editing the original by hand.

Frequently asked questions

Is a binary plist a different file format?: No — it is the same property list object graph with a different serialization. Apple's PropertyListSerialization reads both transparently.
Does converting binary to XML lose anything?: Not with a correct converter. Types and dictionary key order survive the round trip; this editor guarantees both.
Why does git show my plist as binary?: Because it is a binary1 file. Convert it to xml1 to get readable diffs.
Can Xcode open binary plists?: Yes — Xcode's Property List Editor opens both formats and can save either.