## Reliability

Metrics measuring authentication system stability and success rates

[**Authentication Error Rate**  
Authentication Error Rate is the share of authentication attempts that end in an explicit error, helping to pinpoint reliability and UX failures.  
AER=Auth Attempts with Explicit Errors / Total Auth Attempts](/content/kpi/authentication-error-rate/index.html)

[**Login Success Rate**  
Share of login method attempts that result in a successful authenticated session, measured from the moment a user starts a method.  
LSR=Logins succeeded after Method Start / Method Attempts started](/content/kpi/login-success-rate/index.html)

[**Passkey Authentication Success Rate**  
Measures the share of passkey login attempts that reach an authenticated session, including user cancellations and technical failures.  
PASR=Passkey Auth Attempts succeeded / Passkey Auth Attempts started](/content/kpi/passkey-authentication-success-rate/index.html)

## Friction & Speed

Metrics tracking user experience and authentication performance

[**Authentication Drop-Off Rate**  
The percent of authentication attempts that start but do not complete, showing where users abandon the login experience.  
ADoR=(Auth Attempts started − Auth Attempts completed) / Auth Attempts started](/content/kpi/authentication-drop-off-rate/index.html)

[**Time to Authenticate**  
Time to Authenticate measures how long a login takes from starting the auth flow to reaching the authenticated state.  
TTA=Auth completed Timestamp − Auth started Timestamp](/content/kpi/time-to-authenticate/index.html)

## Adoption

Metrics measuring passkey and passwordless adoption progress

[**Login Conversion Rate**  
Share of login attempts where a user starts a login method after being offered at least one option. Measures method choice and early funnel drop off.  
LCR=Login Attempts with Method started / Login Attempts with Method offered](/content/kpi/login-conversion-rate/index.html)

[**Login Engagement Rate**  
Login Engagement Rate measures how often users start a login attempt after being shown a login entry point, indicating intent and funnel health.  
LER=Login Attempts started / Login Offers](/content/kpi/login-engagement-rate/index.html)

[**Passkey Enrollment Rate**  
The share of users who create a passkey after being offered enrollment. It is the leading indicator for passkey adoption and future sign-in gains.  
PER=Enrolled Users / Users offered Passkey Opportunity](/content/kpi/passkey-enrollment-rate/index.html)

[**Passkey Usage Rate**  
Measures the share of successful passkey logins from all successful logins, showing true preference and whether passkeys are the default path.  
PUR=Passkey Logins / Total Logins](/content/kpi/passkey-usage-rate/index.html)

## Fallback & Recovery

Metrics for fallback methods and account recovery flows

[**Password Reset Volume**  
Password Reset Volume tracks how many completed password resets occur per active user per year, helping quantify support load, friction and cost.  
PRV=Total Password Resets / (Active Users ⋅ Time Period in Years)](/content/kpi/password-reset-volume/index.html)

## Business Impact

Metrics connecting authentication to business outcomes

[**Account Takeover Rate**  
How often active accounts are confirmed compromised in a period, reported per 10,000 active accounts to quantify real security harm.  
ATOR=Compromised Accounts / Active Accounts](/content/kpi/account-takeover-rate/index.html)

[**Authentication Support Ticket Rate**  
Portion of all support tickets caused by login and authentication issues, used to quantify auth friction, support cost and improvement impact.  
AST=Auth Related Tickets / Total Support Tickets](/content/kpi/authentication-support-ticket-rate/index.html)

[**Total Authentication Success Rate**  
Total Authentication Success Rate measures how often login attempts end in a completed, authenticated session, including failures and abandonments.  
TASR=Auth Attempts succeeded / Auth Attempts started](/content/kpi/total-authentication-success-rate/index.html)