# How to Clean Junk Files and Optimize Your PC

URL: https://www.mytechnician.tech/tips/clean-junk-files-optimize-pc/
Published: 2026-04-06 | Updated: 2026-08-10 | Author: Ankit Kumar
Tags: Windows 11, Optimization, Storage
Summary: Clear temp folders, browser caches, and leftover installer files on Windows 11 to free disk space and speed up your PC without touching system files.
Recommended app: Quick File Converter — https://www.mytechnician.tech/apps/file-converter/ (Microsoft Store: https://apps.microsoft.com/detail/9MTH938Z7S55?hl=en-us&cid=mytechnician-web). Optional; every step below uses built-in Windows tools.

## The Problem
Temp folders, browser caches, and old installer leftovers pile up over months. The PC still has free space on paper, but everything feels sluggish—updates queue forever and apps take longer to open. This guide is about **clutter**, not a drive that is already completely full.

> **Drive almost full?** If File Explorer shows a red bar on **C:**, start with [how to free up space when C: is full](https://www.mytechnician.tech/tips/free-up-disk-space-c-drive-full-windows-11/). Come back here for routine maintenance once you have breathing room.

## An Honest Expectation
Deleting temp files rarely makes a modern PC faster on its own. What it does is reclaim space, stop updates failing, and remove the clutter that makes real problems harder to spot. The genuine speed wins come from startup programs and background apps—covered at the end of this guide.

The exception is a nearly full SSD. Flash drives slow down markedly above roughly 90% capacity because the controller has less room to work with, so freeing space there does produce a measurable improvement.

## Step 1: Let Windows Do the Safe Part
Storage Sense and Disk Cleanup handle the categories that are genuinely safe to remove, and they know what is still in use.

1. **Settings** → **System** → **Storage** → **Cleanup recommendations**.
2. Work through **Temporary files**, **Large or unused files**, **Files synced to the cloud**, and **Unused apps**.
3. Turn on **Storage Sense** and click into it: set it to run **Every week**, delete files in the Recycle Bin after **30 days**, and clear the Downloads folder **Never** (that setting has caught out a lot of people).

For the deeper categories, run the classic tool as administrator:

1. Press `Win + R`, type `cleanmgr`, press Enter → choose **C:**.
2. Click **Clean up system files**.
3. Tick **Windows Update Cleanup**—often 5–15 GB after a feature update.
4. **Previous Windows installation(s)** frees a lot, but only tick it if you are certain you will not roll back the last feature update.
5. **Delivery Optimization Files** is safe to clear.

## Step 2: Clear Browser Caches
On a machine used daily this is frequently several gigabytes per browser profile.

* **Chrome / Edge:** `Ctrl + Shift + Delete` → time range **All time** → tick **Cached images and files** only. Leave passwords and cookies unticked unless you intend to sign out of everything.
* **Firefox:** `Ctrl + Shift + Delete` → **Everything** → tick **Cache** → **Clear Now**.

If your browser has grown enormous, check for a bloated profile too: [clear your browser cache and cookies](https://www.mytechnician.tech/tips/clear-browser-cache-and-cookies/).

## Step 3: Empty the Temp Folders by Hand
1. Press `Win + R`, type `%temp%`, press Enter. Select all with `Ctrl + A` → **Delete**. Skip anything Windows reports as in use—that is normal and harmless.
2. Repeat with `temp` (no percent signs) for the system temp folder.
3. Empty the **Recycle Bin**.

**Do not** delete folders under `C:\Windows`, `C:\ProgramData`, or `AppData` because a forum post suggested it. That is how people break user profiles and lose saved sign-ins.

## Step 4: Find Forgotten Large Files
1. Open **File Explorer** → **This PC** → in the search box type `size:>1GB` and press Enter.
2. Sort by **Size**.
3. Look for downloaded ISOs, old game installers, video exports, and virtual machine disks. Move what you want to keep to another drive.

For a visual map of where space actually went, **WinDirStat** or **TreeSize Free** shows nested folders far better than Explorer does—game shader caches and old `Windows.old` folders stand out immediately.

## Step 5: Clean Up What Applications Leave Behind
* **Steam:** Steam → Settings → Downloads → **Clear Download Cache**. Also right-click individual games → Properties → Installed Files to spot ones you no longer play.
* **Adobe / video editors:** each keeps a media cache running to many gigabytes; the setting is in the app's own preferences.
* **Windows.old:** removed by Disk Cleanup's **Previous Windows installation(s)** option, or it self-deletes 10 days after an upgrade.
* **Old restore points:** System Protection → **Configure** → reduce **Max Usage** to 5–10%, which trims the oldest automatically.

## Step 6: Where the Actual Speed Comes From
If the goal is a faster PC rather than free space, these two do far more than any file deletion:

* [Disable startup programs to speed up boot](https://www.mytechnician.tech/tips/disable-startup-programs-speed-up-boot/) — fewer things competing at login.
* [Debloat Windows 11](https://www.mytechnician.tech/tips/how-to-debloat-windows-11-remove-bloatware/) — remove preinstalled apps that run all day.

And the full walkthrough: [speed up a slow Windows 11 PC](https://www.mytechnician.tech/tips/speed-up-slow-windows-pc/).

## What Not to Do
* **Don't use registry cleaners.** There is no measurable performance benefit on a healthy Windows install, and a bad clean causes application failures that are hard to trace back.
* **Don't defragment an SSD.** Windows already runs the correct TRIM operation on a schedule; manual defragmentation only adds write wear.
* **Don't install a "PC booster" that runs constantly.** A background optimiser is itself a background process, which is the thing you were trying to reduce.
* **Don't delete `hiberfil.sys` manually.** Turn hibernation off properly with `powercfg /hibernate off` if you never use it.

> **Prefer a one-click pass?** [Ultimate Windows Cleanup Tool](https://www.mytechnician.tech/apps/ultimate-windows-cleanup-tool/) sticks to safe categories—temp files, browser cache, and safe registry leftovers—without touching your documents.

## How Often
Once a month is plenty for most home PCs. Machines that edit video, compile code, or install and remove games frequently benefit from a temp clear every couple of weeks. Set Storage Sense to weekly and most of this happens without you thinking about it.

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Source: https://www.mytechnician.tech/tips/clean-junk-files-optimize-pc/ — My Technician, free Windows 10/11 troubleshooting guides.
Related tool: Quick File Converter (Quick File Converter is an offline file converter for Windows. Convert PDF, Word, Excel, PowerPoint, and images on your PC—no uploads to the cloud.) — https://www.mytechnician.tech/apps/file-converter/
More guides: https://www.mytechnician.tech/llms.txt