Android ID

The Android ID is a unique 64-bit identifier generated by the Android operating system when a device boots for the first time after a factory reset. Alongside the IMEI, it forms one of the two most important hardware-level signals that platforms use to fingerprint devices. Understanding both is essential for anyone doing serious multi-account work on Android, which is why Multilogin Cloud Phones are built on real Android hardware, each with its own genuine Android ID. Unlike the IMEI, which is burned into hardware at manufacture, the Android ID is created in software, but it behaves more like a hardware identifier in practice, because it persists across app installations, SIM card changes, and account logouts, and is not visible to or controllable by the user through normal device settings.

Every Android device has one Android ID. It stays the same whether you install new apps, change phone numbers, clear cache, or switch accounts. The only way to generate a new Android ID is to factory reset the device, and even then, the new ID is tied to the same hardware, which other identifiers (particularly the IMEI) will still identify as the same device.

How the Android ID is generated

When Android sets up a device for the first time, the system generates a random 64-bit value and stores it in the device’s secure settings. This value is the Android ID. It is accessible to apps through the Settings.Secure.ANDROID_ID API, which returns the ID as a hexadecimal string.

From Android 8.0 (Oreo) onward, Google changed how Android ID works: different apps on the same device see different Android IDs for the same device, and the ID is scoped to the app’s signing key. This was a privacy improvement intended to prevent cross-app tracking. However, apps from the same developer (or apps with the same signing key) still see the same Android ID, and platform-level apps like Instagram, TikTok, and Facebook have access to the full Android ID through privileged system access.

How platforms use the Android ID

Platforms use the Android ID as part of a broader device fingerprint, alongside the IMEI, device model, manufacturer, screen resolution, OS version, and other signals. The combination of these signals builds a profile of the specific device that is reliable for account linking and fraud detection even if any individual signal changes.

Account linking. When multiple accounts log in from a device with the same Android ID, platforms associate those accounts. The Android ID is harder to change than cookies or IP addresses, making it a more reliable signal for linking accounts across sessions and even across uninstalls and reinstalls.

Session continuity. Platforms use the Android ID to recognise returning devices, even if the user deletes and reinstalls the app or logs into a different account. A device that previously ran an account banned for policy violations will be recognised on return through its Android ID and other persistent identifiers.

Emulator detection. Android emulators running on desktop hardware have either a missing Android ID, a predictable or default Android ID, or an ID that doesn’t correlate with the device model and IMEI that the emulator is reporting. Platforms use this inconsistency as a detection signal. When an app running on an emulator reports a Samsung Galaxy device model but has a blank or generic Android ID, the mismatch flags the environment as non-genuine. Cloud phones vs mobile emulators covers the full detection picture, including why real hardware avoids these inconsistencies.

Android ID vs IMEI: what’s different

The IMEI is hardware-level, it exists in the device’s modem chip and cannot be changed without hardware modification. The Android ID is software-level, it exists in secure device storage and resets on factory reset.

In practice, the two work together as part of the same device fingerprint. Platforms don’t rely on either alone; they use the combination of IMEI, Android ID, device model, serial number, and other signals to build a confident picture of a specific device. Changing one while the others remain consistent is detectable as an inconsistency, which itself becomes a signal that something unusual is happening.

Android ID and multi-account operations

For anyone running multiple accounts on Android-based social media platforms, the Android ID is one of the key identifiers that determines whether accounts can be genuinely isolated.

When two TikTok accounts, two Instagram accounts, or two Facebook accounts run on the same device, they share an Android ID. Platform systems read this during app sessions and use it to associate the accounts. This association is persistent, it survives logging out, clearing the app data, reinstalling, changing SIM cards, and using a VPN.

The only software-level change that creates a new Android ID is factory resetting the device. But even then, the IMEI and hardware serial number remain identical, so the device is still recognisable as the same hardware.

The practical solution for genuine account isolation is separate hardware, a separate physical device or a cloud phone, for each account. Multilogin Cloud Phones are real Android devices, each with their own Android ID generated at boot on distinct hardware. When Instagram or TikTok reads the Android ID during a session on a cloud phone, they see a unique value tied to genuinely different hardware. The academy explanation of real Android devices in the cloud covers exactly why this distinction matters for platforms with active device fingerprinting.

This is directly relevant for:

Agencies managing client accounts. Running Client A’s Instagram and Client B’s Instagram from the same device links their Android IDs. An account flag on one can associate with the other through the shared device fingerprint. Agencies focused on Instagram ban prevention use per-client device isolation specifically to prevent this cascade.

Multi-account operators. Operators running multiple TikTok or Instagram accounts at scale need each account to have a genuinely independent device fingerprint. The cloud phone vs Android emulator comparison is relevant here: emulators produce synthetic or inconsistent Android IDs that platforms detect. Real cloud phones produce real Android IDs from genuine hardware.

Accounts recovering from bans. An account banned on a platform and then re-registered on the same device carries the same Android ID. Many platforms flag re-registrations from known device fingerprints immediately. Starting from a device with a genuinely new Android ID, and a different IMEI, removes this linkage.

What doesn’t change the Android ID

Common misconceptions about what resets or masks the Android ID:

VPNs. Change the IP address. Have no effect on the Android ID.

Clearing app cache or data. Removes session data and may force re-login. Does not change the Android ID.

Using incognito or private browsers. Browser-level privacy feature. Has no effect on Android system identifiers.

Changing SIM cards. Changes the phone number and carrier. Does not affect the Android ID.

Reinstalling an app. From Android 8+, a reinstall may change the scoped Android ID that specific app sees, but the underlying device Android ID remains the same and is still accessible through privileged APIs.

Key takeaways

The Android ID is a 64-bit unique identifier generated at first boot and stored in secure device settings. It persists across app installs, account changes, and SIM swaps. Platforms use it alongside the IMEI and other signals to fingerprint devices, link accounts, and detect emulated environments. Factory reset generates a new Android ID but doesn’t change hardware identifiers like the IMEI. Genuine account isolation at the device level requires a separate device, and therefore a separate Android ID, for each account.