# Duplicate search

`POST /v1/duplicates/find`

Finds CRM leads, contacts, and companies whose phone number or email address matches the supplied values. Use it before creating a new record to avoid duplicates, when importing data from external sources, and when you need to find a record by phone number.

Bitrix24 API: `crm.duplicate.findbycomm`
Scope: `crm`

## Request fields (body)

| Field | Type | Required | Description |
|------|-----|:-----:|----------|
| `type` | string | yes | Value type to search by: `phone` or `email` |
| `values` | array | yes | List of values to check — phone numbers or email addresses. Maximum 20 values per request |
| `entityType` | string | no | Restrict the search to a single type: `lead`, `contact`, or `company`. If omitted, the search covers all three types |

## Examples

### curl — personal key

```bash
curl -X POST https://vibecode.bitrix24.com/v1/duplicates/find \
  -H "X-Api-Key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "type": "phone",
    "values": ["+12025550123"]
  }'
```

### curl — OAuth application

```bash
curl -X POST https://vibecode.bitrix24.com/v1/duplicates/find \
  -H "X-Api-Key: YOUR_APP_KEY" \
  -H "Authorization: Bearer USER_SESSION_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "type": "phone",
    "values": ["+12025550123"]
  }'
```

### JavaScript — personal key

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/duplicates/find', {
  method: 'POST',
  headers: {
    'X-Api-Key': 'YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    type: 'phone',
    values: ['+12025550123'],
  }),
})

const { success, data } = await res.json()
```

### JavaScript — OAuth application

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/duplicates/find', {
  method: 'POST',
  headers: {
    'X-Api-Key': 'YOUR_APP_KEY',
    'Authorization': 'Bearer USER_SESSION_TOKEN',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    type: 'phone',
    values: ['+12025550123'],
  }),
})

const { success, data } = await res.json()
```

## Response fields

| Field | Type | Description |
|------|-----|----------|
| `success` | boolean | Always `true` on success |
| `data` | object \| array | Matches found, grouped by entity type. Empty array `[]` when there are no matches |
| `data.lead` | array | IDs of leads with matching contact details. Full records: `GET /v1/leads` |
| `data.contact` | array | IDs of contacts with matching contact details. Full records: `GET /v1/contacts` |
| `data.company` | array | IDs of companies with matching contact details. Full records: `GET /v1/companies` |

## Response example

Matches found — `data` contains one key per entity type:

```json
{
  "success": true,
  "data": {
    "lead": [105],
    "contact": [42]
  }
}
```

No matches — `data` comes back as an empty array:

```json
{
  "success": true,
  "data": []
}
```

## Error response example

400 — required parameters not supplied:

```json
{
  "success": false,
  "error": {
    "code": "MISSING_PARAMS",
    "message": "Required: type (\"PHONE\" or \"EMAIL\"), values (string array, max 20)"
  }
}
```

## Errors

| HTTP | Code | Description |
|------|-----|----------|
| 400 | `MISSING_PARAMS` | `type` or `values` not supplied, or `values` is an empty array |
| 400 | `TOO_MANY_VALUES` | More than 20 values in `values` |
| 422 | `BITRIX_ERROR` | Invalid `type` — the error text is returned in the `message` field |
| 403 | `SCOPE_DENIED` | The key lacks the `crm` scope |
| 401 | `TOKEN_MISSING` | The key has no access tokens configured |

Full list of common API errors — [Errors](/docs/errors).

## Known specifics

**A number is matched in any format and against any of the numbers stored on the record.** The values `+1 (202) 555-0123`, `+12025550123`, and `12025550123` all find the same record, no matter how the number is stored in the Bitrix24 account. If a contact has both a work and a mobile phone, the method finds it by either of them. That is why you look up a record by number with this method rather than with the `filter.phone` filter in list or search requests: that filter compares the string against the stored value in full and sees only the record's first number — [Filter by phone and email](/docs/filtering#filter-by-phone-and-email). Pass the number in full: without the country code it is not recognized.

**The `data` type depends on the result.** When there are matches, it is an object keyed by entity type. When there are none, it is an empty array `[]`. Check the type before processing — `Array.isArray(data)` means no matches were found.

**A single value can match several types at once.** If a phone number or email address exists on both a lead and a contact, the response includes both keys with their own IDs. Without `entityType`, check every returned group, not just the first.

## See also

- [Filtering syntax](/docs/filtering)
- [Contacts](/docs/entities/contacts)
- [Leads](/docs/entities/leads)
- [Companies](/docs/entities/companies)
- [API Overview](/docs/entity-api)
- [Errors](/docs/errors)