> For the complete documentation index, see [llms.txt](https://docs.mailtrap.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.mailtrap.io/developers/email-marketing/contacts/contact-fields/create-contact-field.md).

# Create Contact Field

Create new Contact Fields. Please note, you can have up to 40 fields.

```json
{"openapi":"3.1.0","info":{"title":"Contacts","version":"2.0.0"},"tags":[{"name":"Contact Fields","description":"Manage contact fields"}],"servers":[{"description":"Mailtrap API","url":"https://mailtrap.io"}],"security":[{"HeaderAuth":[]},{"BearerAuth":[]}],"components":{"securitySchemes":{"HeaderAuth":{"type":"apiKey","description":"Pass the API token in the Api-Token","in":"header","name":"Api-Token"},"BearerAuth":{"type":"http","scheme":"bearer","bearerFormat":"JWT"}},"schemas":{"ContactField":{"title":"ContactField","type":"object","properties":{"id":{"type":"integer"},"name":{"type":"string","maxLength":80},"data_type":{"type":"string","enum":["text","integer","float","boolean","date"]},"merge_tag":{"type":"string","maxLength":80,"description":"Personalize your campaigns by adding a merge tag. This field will be replaced with unique contact details for each recipient."}}},"UnauthenticatedResponse":{"title":"UnauthenticatedResponse","type":"object","properties":{"error":{"type":"string","description":"Error message"}}},"PermissionsDeniedResponse":{"title":"PermissionsDeniedResponse","type":"object","properties":{"errors":{"type":"string"}}},"UnprocessableEntity":{"title":"UnprocessableEntity","type":"object","properties":{"errors":{"type":"object","description":"Validation errors per attribute. Entire record errors are under `base` key.","additionalProperties":{"type":"array","items":{"type":"string"}}}}},"RateLimitExceededResponse":{"title":"RateLimitExceededResponse","type":"object","properties":{"errors":{"type":"string","description":"Error message"}}},"ErrorResponse":{"title":"ErrorResponse","type":"object","properties":{"errors":{"type":"string","description":"Error message"}}}},"responses":{"UNAUTHENTICATED":{"description":"Returns unauthorized error message. Check your credentials.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/UnauthenticatedResponse"}}}},"PERMISSION_DENIED":{"description":"Returns forbidden error message. Check your permissions.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/PermissionsDeniedResponse"}}}},"LIMIT_EXCEEDED":{"description":"Rate limit exceeded for the current account.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/RateLimitExceededResponse"}}}},"INTERNAL_ERROR":{"description":"Internal error. Retry later or contact support.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/ErrorResponse"}}}}}},"paths":{"/api/contacts/fields":{"post":{"description":"Create new Contact Fields. Please note, you can have up to 40 fields.\n","operationId":"createContactField","summary":"Create Contact Field","tags":["Contact Fields"],"requestBody":{"content":{"application/json":{"schema":{"type":"object","properties":{"name":{"type":"string","maxLength":80},"data_type":{"type":"string","enum":["text","integer","float","boolean","date"]},"merge_tag":{"type":"string","maxLength":80,"description":"Personalize your campaigns by adding a merge tag. This field will be replaced with unique contact details for each recipient."}}}}}},"responses":{"201":{"description":"Contact Field Created.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/ContactField"}}}},"401":{"$ref":"#/components/responses/UNAUTHENTICATED"},"403":{"$ref":"#/components/responses/PERMISSION_DENIED"},"422":{"description":"Returns validation errors.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/UnprocessableEntity"}}}},"429":{"$ref":"#/components/responses/LIMIT_EXCEEDED"},"500":{"$ref":"#/components/responses/INTERNAL_ERROR"}}}}}}
```


---

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