How to increase memory on Xiaomi Mi 9: from garbage cleaning to hardware solutions

The Xiaomi Mi 9 is still a popular smartphone thanks to its powerful hardware and flagship-level camera, but even 64 or 128 GB of internal memory runs out over time — especially if you’re shooting 4K video, installing heavy games, or storing large collections of music. In this article, we’ll look at all the working ways to increase memory on the Mi 9, from software tricks to hardware modifications, given the limitations of the model and current firmware in 2026.

It's important to understand that the Xiaomi Mi 9 doesn't support microSD cards, which is a hardware limitation that you can't get around without physically refining the device, but there are alternative solutions, from optimizing the existing space to connecting external drives, and we tested each method on MIUI 12/14 and Android 10/11 firmware to give clear recommendations.

If you're willing to spend 10-15 minutes setting up, you can free up to 15-20 GB of space without buying additional equipment. OTG-And we'll start with the simplest thing, which is to clean up the system of digital garbage.

1. Clearing cache and unnecessary files: free 3-8 GB

The first step is to delete temporary files that take up space but are not needed to run the smartphone. On the Mi 9, the app cache, residual data after uninstallation and duplicate media files can eat up to 10% of the total memory. Here's how to fix this:

  • 🧹 Cleaning the application cache: go to Settings → Annexes → App management, select the heaviest app (like Facebook or Instagram) and click Clear Cache. Repeat for top-10 place-of-place applications.
  • 🗑️ Removal of residual files: Use the built-in Cleanup utility (the broom icon in the settings menu). APK, logs and empty folders.
  • 🔍 Search for duplicates: install Files by Google from Play Market – the application will automatically find duplicate photos and videos.
  • 📂 Download optimization: check the Download folder (through the Mi File Explorer file manager). APK, archives.

After cleaning it completely, restart your smartphone, which will reset the temporary processes that could have blocked the vacated space. If less than 1 GB of free space has been added after this action, move on to the next section: the problem lies deeper.

⚠️ Note: Do not clean the cache of system applications (e.g. com.android.systemui) manually through ADB Or Root managers. It can cause interface failures. MIUI.

📊 How often do you clear the cache on your smartphone?
Once a week.
Once a month
Only when memory ends
Never.

2. Data transfer to cloud services: pros and cons

Cloud storage is the most versatile way to offload memory, but it has nuances: on the Mi 9, you can use both standard services (Google Drive, Mi Cloud) and specialized services (Amazon Photos for photos, Mega for large files), the main thing is to properly configure autoboot so that you do not do it manually.

ServiceFree volumeAutoloading photoLoading speedFeatures
Google Photo15GB (with Drive)Yeah (tunes in)MediumCompression of photos up to 16 MP at a free tariff
Mi Cloud5GBYes (only for Xiaomi)High (servers in China)Integration with MIUI, but limited in scope
Amazon PhotosUnlimited (for photo)Yes.Low (depending on region)Only for Amazon Prime owners
Mega20GBNo.High (encryption)Suitable for backups, but no autoboot

To transfer photos to Google Photos without loss of quality:

  1. Open the Google Photos app.
  2. Go to Settings → Backup and Synchronization.
  3. Choose “Original Quality” (if there is enough space in Google Drive) or “High Quality” (free compression).
  4. Activate the option “Only via Wi-Fi” to avoid wasting mobile traffic.

For music and documents, it is better to use Google Drive or OneDrive with Files on Demand (available on Android 10+) to trick the system: files will appear in Explorer, but take up space only when opened.

💡

If you’re taking RAW photos on Mi 9, transfer those files to the cloud immediately after shooting – they take up to 50MB each!

3. Use of OTG-drives: external memory without root

Xiaomi Mi 9 supports USB OTG (On-The-Go), which allows you to connect external drives through the adapter USB-C → USB-A. This is the only way to physically expand the memory without disassembling the phone.

  • 💾 Flu-drives USB-A (before 256 GB, FAT32/exFAT).
  • 🖥️ External SSD/HDD separate-feed (port Mi) 9 Does not provide enough current for hard disks).
  • 📱 MicroSD adapters (e.g. SanDisk Ultra Dual Drive).

To use OTG-storage:

  1. Connect the flash drive through the adapter. The notifications will show a message «USB-drive-in».
  2. Click on the notification and select “Use as internal memory” (formatting required!).
  3. After formatting, restart your smartphone. Apps can now be transferred to a flash drive via Settings → Apps → [Select App] → Storage → Change.

⚠️ Note: When formatting a flash drive as internal memory, it will be encrypted and unreadable on other devices. Create a backup of the data before starting!

Speed of operation with OTG-The storage device depends on the class of the flash drive:

  • USB 2.0 (up to 480 Mbps) is suitable for music and documents.
  • USB 3.0/3.1 (up to 5 Gbps) – is needed to run games from an external medium.

On the Mi 9, the USB-C port supports USB 2.0, so don’t overpay for high-speed flash drives – it won’t make a difference.

Buy an adapter USB-C → USB-A|Check the compatibility of the flash drive (FAT32/exFAT)|Create a backup copy of the data|Formatting via smartphone|Move applications manually-->

4. Application optimization: what can be moved or removed

Many apps on the Mi 9 are not only weighted, but also user data (cache, downloads, databases).For example, Telegram can inflate up to 5 GB due to media files, and Google Maps can inflate up to 2 GB due to offline maps. Here's how to reduce their appetites:

Applications that can be safely removed:

  • 🎵 Music streaming services (Spotify, Yandex Music) - cache songs. Delete the cache in the app settings or turn off off offline mode.
  • 🗺️ Maps (Google Maps, 2GIS) – delete offline maps through Settings → Offline maps.
  • 🎮 Games – Use the Clear Data feature to delete saves (but this will reset progress!).

Applications that can be transferred to the OTG:

Not all programs support external memory, but here's a list of those that are verified:

  • 📺 Kodi, VLC — mediaplayer.
  • 📖 Moon+ Reader, FBReader – Readers of books.
  • 🎵 Poweramp, Musicolet – audio players.

To move the application:

  1. Open the Settings → Applications.
  2. Select the desired application and click on “Storage”.
  3. Click “Change” and select an external drive.

If the option is inactive, the application does not support the transfer.

How to remove system applications without root?
On Mi. 9 You can disable (but not remove!) unnecessary system applications through the ADB. For that: 1. Connect your phone to your PC and enable debugging. USB (Settings → The phone. → Version. MIUI — press 7 Once, then return to the additional → For developers). 2. Enter the command: adb shell pm uninstall -k --user 0 com.xiaomi.mipicks Replace com.xiaomi.mipicks with an unnecessary application package (e.g., a package of unneeded apps, com.miui.weather2 weather-wise). ⚠️ After disabling system applications can be updated through the Play Market and returned! 5. Reset to factory settings: extreme measure If after all manipulations of free space remains less 5 GB, and the smartphone is slowing down, and it's time to do Hard Reset, which will delete all the data, including accounts, apps and settings, but it will return Mi. 9 baseline. Before discharge: 🔄 Create a backup through Settings → Additionally. → Backup and reset → Local backup. ☁️ Sync your contacts and photos with Google or Mi Cloud. 📝 Write down the usernames/passwords from the apps (use Google Password Manager or KeePass). Reset instruction: Go to Settings → The phone. → Reset. Select "Erase all data." Enter the password (if installed) and confirm the action. After rebooting, set the phone as new. ⚠️ Note: On the Mi 9 with the Bootloader unlocked, the reset may result in an Anti-Rollback. Check the lock status via fastboot oem device-info before the procedure. After a reset, don't restore the backup right away -- first check how much space has been vacated. Often, older copies contain the same garbage that led to memory shortages. 6. Hardware modifications: risks and opportunities For advanced users, there is a radical way to replace the internal memory. Xiaomi Mi 9 has a chip UFS 2.1 with a volume of 64 or 128 GB. Theoretically, it can be replaced by 256 GB, but this requires: 🔧 Soldering equipment (microscope, thermal air station). 💰 Donor chip with the same wiring (for example, from Mi 9) SE or Redmi K20 Pro). 🛠️ Experience with BGA-It's a chip-based system, and if you get one wrong heat, the motherboard will go bad, it's going to cost you 8,000 to 15,000 dollars to make that modification at the service center. ₽ (You'll lose your phone warranty, depending on the region, and the alternative is to buy a Mi 9 Pro or Mi 10 with a lot of storage, which is often cheaper and safer. If you do decide to upgrade, look for a master with experience with Xiaomi, the memory chips on these models are sensitive to overheating. Before replacing, make a full backup through TWRP (If installed, or Mi Flash Tool. What happens if you interrupt the soldering process? Interrupting the soldering of the memory chip can lead to: - Short circuit on the motherboard (repair costs 20,000 dollars).+ ₽). - Poose. IMEI (A failed camera or Wi-Fi module (memory chips are often connected to other controllers). - In 80% of cases, a failed soldering leads to a complete replacement of the board (~60% of the cost of a new phone). 7. Alternative solutions: what to do if nothing works If all methods have been tried and there is still not enough memory, consider these options: 📱 Buying a new phone: Xiaomi Mi 11 or POCO F4 256 GB of memory costs from 25,000 ₽ (2026). ☁️ Cloud PC Rent: Services like Shadow or GeForce NOW Allows you to play heavy games without downloading to your phone. 🖥️ Use your phone as a secondary device: Transfer your main tasks to your tablet or laptop, and use the Mi 9 for calls and instant messengers. 🔄 Sale/Exchange: In the secondary market, the Mi 9 can be exchanged for a model with a larger memory (for example, the Redmi Note 12 Pro).+). If you are attached to the Mi 9 emotionally or because of specific features (e.g., the scaling up of your body, IR-Port for control equipment, try combining methods: Store media files in the cloud. Use OTG-Clean the cache regularly (once a week), an approach that will allow you to "hold on" for another 1-2 years without upgrading. FAQ: Frequent questions on memory enhancement on Xiaomi Mi 9 Can I install a microSD card in Xiaomi Mi 9? No, Xiaomi Mi 9 does not support microSD cards at the hardware level - there is no slot in the phone. The only way to expand memory is to use OTG-So, what's the reason why is it that the cache is cleaned, that the memory is not freed for long? It's because of background processes. MIUI For example, Facebook and Instagram cache data anew every time they open. Solution: Limit background activity to Settings. → Battery → Battery optimization. Turn off autoload media in instant messengers. Can you transfer WhatsApp to your messaging app? OTG-No, WhatsApp doesn't support external memory because of security policy, but you can: Move media files (photo/video) from the folder. WhatsApp/Media Use Easy Mode in WhatsApp settings to reduce the weight of the app. How do you know which files take up the most space? Use the built-in tool MIUI: Open the Settings. → Click on "Memory Analysis" (may take time) 1–2 minute). The system will show the largest files and folders, sorted by size, and the alternative is the DiskUsage app from Play Market, which visualizes the space occupied. OTG-If you take it out and you put it back in, if the flash drive is formatted as internal memory, you can't just retrieve it, and it will lead to reading errors. → Storage, click on the name. OTG-You can select "Extract" and wait for the notification "Device can be safely removed." If you pull the flash drive without turning it off, you may need to restart the next time you connect.