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Customer success metrics glossary: 25 terms in plain English

By Draft First. Updated October 2026

Customer success has a lot of three-letter metrics, and teams often use the same word for different things. Here is a plain-English glossary you can share with your team, your manager or a new hire. Where there's a formula, it's included. Where teams commonly disagree, we say so.

Retention and revenue

ARR (annual recurring revenue)

The yearly value of active subscriptions. MRR times 12.

MRR (monthly recurring revenue)

The monthly value of active subscriptions. One-time fees don't count.

Gross revenue retention (GRR)

(Starting revenue minus churn minus downgrades) divided by starting revenue. Never above 100%. Shows how well you keep what you had.

Net revenue retention (NRR)

Same as GRR, plus expansion. Can go above 100%. Try the NRR and GRR calculator.

Customer churn rate (logo churn)

Customers lost divided by customers at the start of the period. Try the churn rate calculator.

Revenue churn

Revenue lost to cancellations and downgrades divided by starting revenue.

Expansion revenue

New revenue from existing customers: more seats, upgrades, add-ons.

Contraction

Revenue lost from customers who stay but pay less.

Renewal rate

Renewals signed divided by renewals due in the period. Count by logo, revenue, or both, and say which.

Customer lifetime value (LTV)

Average revenue per account times gross margin, divided by churn rate. A rough guide, not a promise.

Adoption and value

Time to value (TTV)

Days from signature to the customer's first real result. Define "first value" per product before you measure it.

Time to first value vs full onboarding

First value is the first win. Onboarding complete is when the setup work is done. They're different dates.

Active users

Users who did something meaningful in a period (daily, weekly or monthly). Agree on what counts as "active".

License utilization

Active users divided by seats bought. Low utilization near renewal is a common warning sign.

Feature adoption

Share of accounts or users using a given feature. Most useful for the two or three features tied to value.

Health and risk

Customer health score

A simple rating, often Green, Yellow or Red, built from a few warning signs. See how to build one.

At-risk account

An account showing enough warning signs to need a plan. Set a clear rule, like two signs at once.

Champion

The person inside the customer who pushes for your product. Losing one is a top churn reason.

Executive sponsor

The senior person on their side who owns the outcome and the budget.

Churn reason code

A label for why an account left. See the churn reason code list.

Feedback and support

NPS (Net Promoter Score)

Percent of 9 and 10 scores minus percent of 0 to 6 scores, from "how likely are you to recommend us?" Ranges from minus 100 to 100.

CSAT (customer satisfaction)

Share of positive answers to "how satisfied were you?", usually after a ticket or a milestone.

CES (customer effort score)

How easy it was to get something done. Lower effort tends to mean more loyalty.

First response time

Time from a ticket being opened to the first human reply.

Escalation rate

Share of tickets escalated to a higher tier or to leadership. Watch it per account, not just overall.

Which ones to actually track

Don't track all 25. Most CS teams do well with GRR, NRR, logo churn, time to value and a simple health score. See the 8 metrics worth tracking for why.

Questions

What is the difference between NRR and GRR?

GRR counts only what you kept after churn and downgrades, so it can't go above 100%. NRR adds expansion, so it can.

What is logo churn?

Logo churn is the share of customers, by count, who left in a period, regardless of how much they paid.

What does time to value mean in customer success?

The time from signing to the customer's first real result with your product.