> ## Documentation Index
> Fetch the complete documentation index at: https://docs.lusha.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Score contacts and companies by signal activity

> Turn active buying signals into a single [0, 1] score per contact or company, with the signal breakdown behind it - up to 100 records per call.

Signal Score collapses a record's active buying signals into one number you can sort and threshold on. Where [Signals](/signals/overview) tells you *what* is happening, Signal Score tells you *how much* is happening - so you can rank a list rather than read it.

Every score comes with the signal breakdown behind it, so a high score is always explainable.

<CardGroup cols={2}>
  <Card title="Score Contacts" icon="user" href="/api-reference/signals/score-contacts-by-signal-activity">
    `POST /v3/contacts/signal-score` - up to 100 contacts per call.
  </Card>

  <Card title="Score Companies" icon="building" href="/api-reference/signals/score-companies-by-signal-activity">
    `POST /v3/companies/signal-score` - up to 100 companies per call.
  </Card>
</CardGroup>

## The score

`signalScore` is a value in `[0, 1]` reflecting the fraction of the record's active signals. Alongside it you get:

* `signalTypes` - the active signal breakdown
* `noActiveSignals` - set when the record resolved but has nothing currently firing

## Identifying records

Identity is resolved server-side before scoring. **This is identity resolution only - no PII is revealed and no enrichment credits are spent on it.**

<Tabs>
  <Tab title="Contacts">
    Provide one of:

    * `id` - encrypted Lusha contact ID
    * `linkedinUrl`
    * `email`
    * `firstName` + `lastName` + (`companyName` or `companyDomain`)
  </Tab>

  <Tab title="Companies">
    Provide exactly one of:

    * `id`
    * `domain`
    * `name`
    * `email`
  </Tab>
</Tabs>

## Reading the results

Each entry in the response is one of three outcomes:

| Outcome         | Meaning                                                              |
| --------------- | -------------------------------------------------------------------- |
| **Scored**      | `signalScore`, `signalTypes`, and `noActiveSignals` are populated.   |
| **`NOT_FOUND`** | Identity resolution failed for the identifier you supplied.          |
| **`NO_SCORE`**  | The record resolved, but the scoring engine returned nothing for it. |

<Note>
  `NOT_FOUND` and `NO_SCORE` mean different things and deserve different handling. `NOT_FOUND` is an identifier problem worth retrying with a better identifier; `NO_SCORE` means the record is genuinely unscored right now.
</Note>

## Billing

1 credit is charged per scored record. Entries returned as `NOT_FOUND` or `NO_SCORE` are not charged.

## Related pages

* [Signals overview](/signals/overview) - the underlying signal types
* [Contact signals](/signals/contact-signals) and [company signals](/signals/company-signals)
* [Buying Group](/buying-group/overview) - who to contact once you've picked the account