Asks the system to drop cached files until the given amount of free space exists.
pm trim-caches <free space target>[K|M|G]| Token | Meaning |
|---|---|
| <target> | How much free space to aim for. The suffix is a power of 1024, so `512G` means 512 GiB — deliberately more than any phone has, i.e. "drop everything you consider disposable". |
pm trim-caches 512GFree every cache the system is willing to drop.
pm trim-caches 2GStop once there are 2 GiB free.
Nothing. Success is silence: the command waits for the platform to finish and returns without printing, and it never reports how much it freed — not even whether it freed anything. The only honest "you got N MB back" is to measure free space before and after with `df` or `dumpsys diskstats`. Anything printed at all is a refusal: an invalid suffix, a missing number, or an exception when the build did not grant the shell the permission this needs.
| Field | Meaning |
|---|---|
| (no output) | The trim ran. How much it freed is not reported. |
| Invalid suffix: … | The size argument was not understood. |
| Error: expected number at: … | The size argument was not a number. |
Android Storage Analyzer runs this command over USB and parses what comes back — a Chromium browser, no SDK, nothing uploaded.
Commands that turn up in the same session as pm trim-caches.
| Command | What it does |
|---|---|
| pm clear | Wipes an app's data — or, on Android 13 and later, only its cache. |
| dumpsys diskstats | Free space per partition, a disk write latency check, and a cached per-app breakdown of what is using storage. |
| df | Reports free and used space per mounted filesystem. |
| du | Reports how much disk space a directory tree occupies. |
| Command | What it does |
|---|---|
| pm list packages | Lists installed packages, optionally with the APK path, uid, version code and installer. |
| pm path | Prints the absolute paths of the APK files that make up an installed package. |
| pm uninstall | Removes a package, or removes it for one Android user only — which is how a preinstalled app is disposed of without root. |
| pm disable-user | Switches a package off for one Android user without removing it — the reversible alternative to uninstalling. |
| pm install | Installs one APK that is already on the device, which is what `adb install` does under the hood. |
| pm install-create | Opens an install session so several APKs — a base plus its splits — are installed as one atomic unit. |
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.
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.
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.
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.
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.