A credit score for your email sending reputation.

The INBXR Score is a single 0–100 number, graded A–F, that tells you how healthy your email program is — and where it's headed. It's built on the 7 Inbox Signals every list broadcasts, and it's the standard we use to evaluate senders, certify partners, and power the public sender registry.

Think of it the way lenders think of a FICO score. One portable number that anyone can pull, that summarizes risk, and that you can actively improve. Except this one is about whether your next campaign reaches the inbox.

How the score reads

A 0–100 composite of the 7 Inbox Signals, rounded to an integer and mapped to a letter grade. The bands are fixed and published — the same scale for every sender, every time.

Full score vs. Lite score

Five of the seven signals read your list's per-contact engagement — data only your ESP holds. So the score comes in two honest tiers. We never present one as the other.

The 7 Inbox Signals inside the score

Each signal carries a fixed weight. Domain-side signals (highlighted) are what the Lite score can read for any domain. See the full methodology for every formula and data source.

A versioned, stable standard

A standard is only trustworthy if its methodology is stable and its changes are documented. Weights and formulas are versioned; we publish a changelog rather than silently re-tuning.