df

read-only

Reports free and used space per mounted filesystem.

Command: adb shell df
Commands: Files and storage
Risk: read-only

Syntax

df [-k] [-h] [-H] [-P] [-i] [<path>]

Flags and arguments

Token	Meaning
-k	1024-byte blocks, and the flag that pins the header to a label you can rely on.
-h	Human-readable, base 1024.
-H	Human-readable, base 1000.
-P	POSIX output: 512-byte blocks, and the percentage column is named Capacity.
-i	Count inodes instead of bytes. The columns then hold inode counts.

Examples

```
df -k /data
```
Free space on the userdata partition, in KiB.
```
df -k
```
Every mounted filesystem.
```
df -h /data
```
Quick to read by eye; not a number to compute with.

Reading the output

Sample output

Filesystem     1K-blocks      Used Available Use% Mounted on
/dev/block/dm-9 111222333  98765432  12345678  89% /data

The header line *is* the unit declaration, and it is the only place the unit appears — so read the columns through it rather than by position. `1K-blocks` means 1024 bytes each, `512-blocks` means 512, `Size` means the value was humanised, and `Inodes` means the numbers are not bytes at all.

Output fields

Field	Meaning
1K-blocks	Total size in 1024-byte blocks. `-k` and the default.
512-blocks	Total size in 512-byte blocks. What `-P` produces.
Size / Avail	Humanised values, from `-h` or `-H`. Three significant digits.
Use% / Capacity	The percentage used. The label depends on the flags.
Mounted on	The mount point. Two words in the header, one column in the rows.
-	A filesystem that could not be measured. Not zero.

Version and vendor notes

`-h` and `-H` are indistinguishable in the output: both print the same column labels and the same unit letters, and only the kilobyte suffix reveals its case. A humanised reading cannot tell you which base produced it, so ask for blocks when it matters.
The shell merges standard error into the output, so a line like `df: /mnt/media_rw/0000-1111: No such file or directory` arrives in the middle of the table and has enough words in it to look like a row. A real row has numbers where the header promised numbers.
On Android 5.1 and earlier `df` is a different implementation with a different header and no separate mount-point column, and it does not understand `-k` — it treats the flag as a path.

We have a UI for this

Android Storage Analyzer runs this command over USB and parses what comes back — a Chromium browser, no SDK, nothing uploaded.

Open Android Storage Analyzer

Related commands

Commands that turn up in the same session as df.

Command	What it does
du	Reports how much disk space a directory tree occupies.
dumpsys diskstats	Free space per partition, a disk write latency check, and a cached per-app breakdown of what is using storage.
pm trim-caches	Asks the system to drop cached files until the given amount of free space exists.

More Files and storage commands

Command	What it does
find	Walks a directory tree and prints what matches — big files, empty folders, leftovers.
rm	Deletes a file or a directory tree on the device.

Checked against AOSP, toybox and kernel sources while writing the parsers behind our Web ADB tools. Where a behaviour genuinely varies by Android version or manufacturer, this page says so instead of giving a number that would be wrong on half the phones out there.

Frequently asked questions

How do I run an adb shell command?

Switch on developer options and USB debugging on the phone, plug it in, then run `adb shell <command>` from a machine with platform-tools installed — or run `adb shell` on its own to get an interactive prompt and type the command without the prefix. If the command produces binary output, such as a screenshot, use `adb exec-out` instead of `adb shell`: the plain shell service attaches a terminal, which rewrites newline bytes and corrupts the data.

Do adb shell commands need root?

Not the ones on this reference. They run as the `shell` user, which can manage packages for its own Android user, read most `dumpsys` services, write the settings provider, inject input and read shared storage. Root is only needed for things this reference deliberately avoids — reading another app's private data (except through `run-as` on a debuggable build), writing system partitions, or reading `/data/anr` directly.

Why does the output look different on my phone?

Either the Android version or the manufacturer. Some flags and fields arrived in a specific release, and those are noted per command. The rest is OEM patching, which hits `dumpsys` hardest: a dump is debug output whose text is whatever the service author last printed, and manufacturers change it and backport their changes. Read fields by name rather than by position, and treat an unfamiliar shape as a difference rather than as a failure.

Can I run this from a browser instead of a terminal?

For many commands, yes — the Web ADB tools on this site talk to a phone over WebUSB from a Chromium-based desktop browser, with no SDK installed and nothing uploaded. Each page links to the tool that runs its command, when one exists. Two limits are worth knowing: only one program can hold the ADB interface at a time, so a desktop `adb server` has to be stopped first, and `adb forward` and `adb reverse` cannot work in a browser at all.

Would rather click than type? The Web ADB Toolkit runs commands like this from a browser over USB. Or browse every command.