Crucial Warning: Check your phone model number in Settings -> About Phone or on the back sticker. Packages on this page are made for the ZenFone Max (M1) models ZB555KL and ZB556KL (codename ASUS_X00P). Do not attempt to flash packages made for the ZenFone Max Pro (M1) (ASUS_X00T).
Download Firmware for ASUS ZenFone Max (M1)
ZB556KL_UL-ASUS_X00P-WW-15.00.2007.122-user.zip
Final official stock update for model ZB556KL. Copy to the root of your internal storage or install through stock recovery.
⬇️ Download via Google DriveWW_ZB555KL_15.00.1905.101.rar
Official factory service archive for model ZB555KL. Useful for unbricking and restoring corrupted partitions.
⬇️ Download via AFHZB555KL_15.00.1902.98_DL-131993064017882365.zip
Official stock firmware ZIP for model ZB555KL. Verified clean factory package with MD5 check.
⬇️ Download via AFHFlashing Overview for ASUS ZenFone Max (M1)
- Confirm your phone model is ZB555KL or ZB556KL (ASUS_X00P)
- Download the matching firmware zip file for your exact model
- Copy the zip file directly to the main folder (root directory) of your phone internal storage or microSD card
- Disconnect USB and restart the phone; tap "System Update File Detected" when the notification pops up
- If the phone will not boot into Android, boot into Recovery Mode (Volume Down + Power) and select "Apply update from microSD"
Expand preparation checklist for ASUS ZenFone Max (M1)
- Check your exact model number (ZB555KL or ZB556KL) under Settings or on the back label.
- Make sure your battery has at least 40% charge before you start.
- If updating via SD card: copy the UL-*.zip file directly to the root of your microSD card or internal storage.
- If flashing via computer: install ASUS Android USB drivers on your Windows PC.
- Back up your photos, contacts, and personal data if the phone still turns on.
Compatibility & Bootloader Notes
Official ASUS user update packages (UL-*.zip) flash through stock recovery without needing an unlocked bootloader. Placing the file in the root of the internal storage triggers an automatic update prompt.
Ready to Flash This Firmware?
Full step-by-step instructions for ASUS ZenFone Max (M1), including prerequisites, error fixes, and screenshots, are on FlashGuideHub's ASUS Flash Tool guide.
Can also be flashed via ADB Sideload: Open ADB Sideload Guide →
Frequently Asked Questions
This page covers the ASUS ZenFone Max (M1) models ZB555KL and ZB556KL (codename ASUS_X00P / X00PD). Both use Qualcomm Snapdragon 425/430 processors and share the same 5.5-inch chassis.
Download the zip file and do not unzip it. Copy it straight to the root folder of your phone internal memory or microSD card. Restart your phone. A notification will appear saying "System Update File Detected". Tap it and follow the on-screen instructions to update.
Yes. Copy the firmware zip file to a microSD card. Put the card into your phone. Turn off the phone, then hold Volume Down + Power until you enter Recovery Mode. Choose "Apply update from microSD", select the file, and wait for it to complete.
Installing a standard official update via internal storage or recovery does not wipe user data. However, if your phone is stuck in a boot loop and you need to select "Wipe data/factory reset" in recovery mode, all personal files will be erased.