# Watermarking specific pages

Use the pages selector to stamp only a cover, an appendix, or every page but the first with a text or image watermark.

By default a watermark lands on every page. The `pages` field narrows that to a
precise subset — a cover page, an appendix, everything but the first page — so
you can stamp exactly where you need to. Both [Add text
watermark](/docs/api/add-text-watermark-to-pdf) and [Add image
watermark](/docs/api/add-image-watermark-to-pdf) accept it, and it works the same
way on every action that takes a `pages` field.

## The `pages` selector

`pages` is a comma-separated list of 1-based page numbers and ranges. It is
treated as a **set**: order and duplicates are ignored, and pages are always
stamped in document order. Omitting it selects every page. See [Selecting
pages](/docs/api/selecting-pages) for the complete syntax.

| Goal | `pages` value |
| --- | --- |
| The cover page only | `1` |
| Every page but the first | `2..` |
| Every page but the last | `..-2` |
| The last page only | `-1` |
| An appendix from page 8 onward | `8..` |
| A specific set of pages | `1..3,5` |
| The last three pages | `-3..-1` |

## Stamp every page but the cover

A common request: a running confidentiality mark on the body of a document, but
not over the title page. Select `pages=2..` — page 2 through the last page.

<CodeGroup>

```bash title="cURL"
curl https://api.pdfblocks.com/v1/add_text_watermark \
  -H 'X-API-Key: your_api_key' \
  -F file=@input.pdf \
  -F line_1='CONFIDENTIAL' \
  -F pages='2..' \
  -o watermarked.pdf
```

```python title="Python"
# pip install requests
import requests

with open('input.pdf', 'rb') as file:
    response = requests.post(
        'https://api.pdfblocks.com/v1/add_text_watermark',
        headers={'X-API-Key': 'your_api_key'},
        files={'file': file},
        data={'line_1': 'CONFIDENTIAL', 'pages': '2..'},
    )

response.raise_for_status()
with open('watermarked.pdf', 'wb') as output:
    output.write(response.content)
```

```javascript title="Node.js"
// Node.js 18+
import { readFile, writeFile } from 'node:fs/promises';

const body = new FormData();
body.set('file', new Blob([await readFile('input.pdf')]), 'input.pdf');
body.set('line_1', 'CONFIDENTIAL');
body.set('pages', '2..');

const response = await fetch('https://api.pdfblocks.com/v1/add_text_watermark', {
  method: 'POST',
  headers: { 'X-API-Key': 'your_api_key' },
  body,
});

if (!response.ok) throw new Error(`Request failed: ${response.status}`);
await writeFile('watermarked.pdf', Buffer.from(await response.arrayBuffer()));
```

```php title="PHP"
<?php
$ch = curl_init('https://api.pdfblocks.com/v1/add_text_watermark');
curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_HTTPHEADER => ['X-API-Key: your_api_key'],
    CURLOPT_POST => true,
    CURLOPT_POSTFIELDS => [
        'file' => new CURLFile('input.pdf', 'application/pdf'),
        'line_1' => 'CONFIDENTIAL',
        'pages' => '2..',
    ],
]);

$pdf = curl_exec($ch);
if (curl_getinfo($ch, CURLINFO_HTTP_CODE) === 200) {
    file_put_contents('watermarked.pdf', $pdf);
}
```

```ruby title="Ruby"
# gem install http
require 'http'

response = HTTP
  .headers('X-API-Key' => 'your_api_key')
  .post('https://api.pdfblocks.com/v1/add_text_watermark', form: {
    file: HTTP::FormData::File.new('input.pdf'),
    line_1: 'CONFIDENTIAL',
    pages: '2..',
  })

File.write('watermarked.pdf', response.body) if response.status.success?
```

```go title="Go"
package main

import (
	"bytes"
	"io"
	"mime/multipart"
	"net/http"
	"os"
)

func main() {
	var buf bytes.Buffer
	form := multipart.NewWriter(&buf)

	file, _ := os.Open("input.pdf")
	defer file.Close()
	part, _ := form.CreateFormFile("file", "input.pdf")
	io.Copy(part, file)

	form.WriteField("line_1", "CONFIDENTIAL")
	form.WriteField("pages", "2..")
	form.Close()

	req, _ := http.NewRequest("POST",
		"https://api.pdfblocks.com/v1/add_text_watermark", &buf)
	req.Header.Set("Content-Type", form.FormDataContentType())
	req.Header.Set("X-API-Key", "your_api_key")

	res, _ := http.DefaultClient.Do(req)
	defer res.Body.Close()

	out, _ := os.Create("watermarked.pdf")
	defer out.Close()
	io.Copy(out, res.Body)
}
```

```csharp title="C#"
using var client = new HttpClient();
client.DefaultRequestHeaders.Add("X-API-Key", "your_api_key");

using var form = new MultipartFormDataContent
{
    { new ByteArrayContent(File.ReadAllBytes("input.pdf")), "file", "input.pdf" },
    { new StringContent("CONFIDENTIAL"), "line_1" },
    { new StringContent("2.."), "pages" },
};

var response = await client.PostAsync(
    "https://api.pdfblocks.com/v1/add_text_watermark", form);
response.EnsureSuccessStatusCode();
await File.WriteAllBytesAsync(
    "watermarked.pdf", await response.Content.ReadAsByteArrayAsync());
```

</CodeGroup>

## More targeting patterns

The only thing that changes between these is the `pages` value. Each snippet
writes to a different output file.

<CodeGroup>

```bash title="Cover page only"
# pages=1 — stamp just the title page.
curl https://api.pdfblocks.com/v1/add_text_watermark \
  -H 'X-API-Key: your_api_key' \
  -F file=@input.pdf \
  -F line_1='DRAFT' \
  -F pages='1' \
  -o cover.pdf
```

```bash title="Every page but the last"
# pages=..-2 — the first page through the second-to-last.
curl https://api.pdfblocks.com/v1/add_text_watermark \
  -H 'X-API-Key: your_api_key' \
  -F file=@input.pdf \
  -F line_1='DO NOT DISTRIBUTE' \
  -F pages='..-2' \
  -o body.pdf
```

```bash title="An appendix onward"
# pages=8.. — page 8 to the end.
curl https://api.pdfblocks.com/v1/add_text_watermark \
  -H 'X-API-Key: your_api_key' \
  -F file=@input.pdf \
  -F line_1='APPENDIX' \
  -F pages='8..' \
  -o appendix.pdf
```

```bash title="Selected pages"
# pages=1..3,5 — pages 1, 2, 3, and 5.
curl https://api.pdfblocks.com/v1/add_text_watermark \
  -H 'X-API-Key: your_api_key' \
  -F file=@input.pdf \
  -F line_1='REVIEW COPY' \
  -F pages='1..3,5' \
  -o review.pdf
```

</CodeGroup>

## Image watermarks target the same way

An image watermark uses an identical `pages` field — pass a PNG or JPEG in the
`image` field alongside `file`. This stamps a logo on the cover page only:

<CodeGroup>

```bash title="cURL"
curl https://api.pdfblocks.com/v1/add_image_watermark \
  -H 'X-API-Key: your_api_key' \
  -F file=@input.pdf \
  -F image=@logo.png \
  -F pages='1' \
  -o watermarked.pdf
```

```python title="Python"
# pip install requests
import requests

with open('input.pdf', 'rb') as file, open('logo.png', 'rb') as image:
    response = requests.post(
        'https://api.pdfblocks.com/v1/add_image_watermark',
        headers={'X-API-Key': 'your_api_key'},
        files={'file': file, 'image': image},
        data={'pages': '1'},
    )

response.raise_for_status()
with open('watermarked.pdf', 'wb') as output:
    output.write(response.content)
```

```javascript title="Node.js"
// Node.js 18+
import { readFile, writeFile } from 'node:fs/promises';

const body = new FormData();
body.set('file', new Blob([await readFile('input.pdf')]), 'input.pdf');
body.set('image', new Blob([await readFile('logo.png')]), 'logo.png');
body.set('pages', '1');

const response = await fetch('https://api.pdfblocks.com/v1/add_image_watermark', {
  method: 'POST',
  headers: { 'X-API-Key': 'your_api_key' },
  body,
});

if (!response.ok) throw new Error(`Request failed: ${response.status}`);
await writeFile('watermarked.pdf', Buffer.from(await response.arrayBuffer()));
```

</CodeGroup>

<Tip>
  The same `pages` selector drives the page-oriented actions too — [Extract
  pages](/docs/api/extract-pages-from-pdf), [Remove
  pages](/docs/api/remove-pages-from-pdf), and [Rotate
  pages](/docs/api/rotate-pages-in-pdf) all read it the same way. Learn it once,
  reuse it everywhere.
</Tip>

## Related

<CardGroup cols={2}>

<Card title="Selecting pages" href="/docs/api/selecting-pages">
  The full page-range syntax, including negative indices.
</Card>

<Card title="Add a text watermark" href="/docs/api/add-text-watermark-to-pdf">
  Templates, colors, opacity, and margins.
</Card>

<Card title="Add an image watermark" href="/docs/api/add-image-watermark-to-pdf">
  Stamp a PNG or JPEG logo instead of text.
</Card>

<Card title="Extract pages" href="/docs/api/extract-pages-from-pdf">
  Pull out a subset of pages with the same selector.
</Card>

</CardGroup>