How to change Authenticator to 6 digits

Microsoft Authenticator can display either 6‑digit or 8‑digit one-time passwords (OTPs), depending on how the account was originally configured by the service (for example, Azure MFA, Microsoft account, or another site using TOTP).

The number of digits is defined by the server-side MFA/TOTP configuration, not by a setting in Microsoft Authenticator. If an account in the app is showing 8‑digit codes, there is no client-side option in Microsoft Authenticator to change that specific account to 6 digits. To use 6‑digit codes instead of 8‑digit codes, the MFA configuration for that account must be reset and reconfigured on the service side to use 6‑digit TOTP codes.

If the 8‑digit codes from Microsoft Authenticator are not being accepted where a 6‑digit code is requested, the MFA profile is likely misaligned or stuck. In such cases, the documented resolution is to reset MFA from the identity provider side (for example, via Microsoft Entra ID by requiring re‑registration of MFA, or by contacting Microsoft support/Data Protection team to reset MFA for the account) and then re‑register the authenticator method so that the correct code format is enforced.

References:

• Reset Personal Azure MFA - Microsoft Q&A
• Microsoft Authenticator app doesn't show 6-digit OTP code - Microsoft Q&A