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

# Custom signatures

> Sign every postcard with your own handwritten signature, traced from a scan.

Upload a scan of your signature once. Paperjoy traces it into pen strokes, and the robot signs your postcards with it.

![A postcard with a short message and a real, flowing handwritten signature underlined in the bottom left corner.](https://mintcdn.com/paperjoy/F1MJj4Vyrx0MCZIR/images/postcards/card-custom-signature-en.webp?fit=max\&auto=format\&n=F1MJj4Vyrx0MCZIR\&q=85\&s=dbee88db733e590d990da027383cd92f)

## Plans

| Plan | Custom signatures |
| - | - |
| Start | — |
| Pro | 1 |
| Business | Up to 3 |

Compare plans in [Billing](https://paperjoy.co/billing). If you move to a plan with fewer signatures, the extra ones can't be used on new postcards.

## Add a signature

**1. Scan your signature**

Sign in dark ink on plain white paper and take a sharp, well-lit photo or scan. Crop it close to the signature. JPG, PNG, and WebP files up to 5 MB work.

**2. Upload it**

Open [**Ustawienia → Podpisy**](https://paperjoy.co/settings/signatures) (Settings → Signatures). Enter a name, such as your own, choose the file, and click **Prześlij podpis** (Upload signature).

**3. Wait for activation**

We trace the signature by hand. It is ready within 3 business days, and we email you when it's active.

Scans can only be uploaded in the app. The API lists, retrieves, and deletes signatures, but doesn't accept files.

![The Signatures settings page with the upload form and an active signature named Marta Nowak.](https://mintcdn.com/paperjoy/F1MJj4Vyrx0MCZIR/images/app/signatures.webp?fit=max\&auto=format\&n=F1MJj4Vyrx0MCZIR\&q=85\&s=a6c42ef198768ba791b709c5d6a990d2)

## Use it

> [tab] Editor
>
> Under **Podpis** (Signature), open the **Własny podpis** (Custom signature) tab and pick your signature.

> [tab] API
>
> Find the signature ID:
>
> ```bash theme={null}
> curl https://paperjoy.co/api/signatures \
>   --header "Authorization: Bearer $PAPERJOY_API_KEY" \
>   --header "Accept: application/json"
> ```
>
> ```json theme={null}
> {
>   "data": [
>     {
>       "id": "sig_ZeXOkSQjTp",
>       "name": "Marta Nowak",
>       "status": "active",
>       "created_at": "2026-10-10T09:00:00+00:00",
>       "updated_at": "2026-10-12T11:20:00+00:00"
>     }
>   ]
> }
> ```
>
> Then send `signature_id` instead of `signature` when you [create](https://docs.paperjoy.co/en/postcards/create.md) or [preview](https://docs.paperjoy.co/en/postcards/preview.md) a postcard:
>
> ```json theme={null}
> {
>   "content": "Thank you for being with us for a whole year!",
>   "signature_id": "sig_ZeXOkSQjTp",
>   "font_id": "font-1"
> }
> ```
>
> Only signatures with `"status": "active"` can be used. A signature that is still `in_progress`, deleted, or not included in your plan returns a `422` error on `signature_id`.

> [tab] MCP
>
> Ask your assistant to use your signature. It calls `list-signatures-tool` to find the ID and passes it to `create-postcard-tool`.

## Delete a signature

Click the trash icon next to the signature in the app, or call [`DELETE /api/signatures/{id}`](https://docs.paperjoy.co/en/reference/introduction#endpoints). The signature disappears from the list right away and can't be used on new postcards. Postcards that are already ordered are still signed with it. Paperjoy permanently deletes the signature and its files after 30 days.


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