PDF Text Watermark Generator is a powerful and user-friendly software tool designed to seamlessly add customizable text watermarks to PDF (Portable Document Format) files. This functionality not only helps protect sensitive documents and establish ownership but also ensures professional branding and confidentiality across all your PDF content. The tool efficiently handles both single-page and multi-page PDFs, offering a wide range of customization options, including watermark text, font style, size, color, opacity, position, rotation, and page range. With this advanced solution, users can effortlessly enhance document security, maintain a polished appearance, and convey important information with clear, professional text watermarks, making it an essential tool for businesses, educators, and professionals alike.
Try it in Live Tool| Feature | Us | Other APIs |
|---|---|---|
| Credit-Based Pricing | Yes | Limited or confusing |
| Transparent Billing | Yes | Surprise charges |
| Dev-Focused Docs | Yes | Sparse examples |
| Free Credits | Yes | Paywall from day 1 |
| Fast Support | Yes | 3+ day wait time |
This example will sign your document with a Nutrient certificate.

Sign up and receive 100 credits for free, or log in to automatically add your API key to sample code. If you are not sure how credits are consumed read more in our pricing documentation , or check out this guide on calculating credit usage.

Add a PDF named document. pdf to your project folder. You can use our sample document.

Copy the code and run it from the same folder you added the files to. For more information, see our language-specific getting started guides.

Open result.pdf in your project folder to view the results.
curl -X POST "https://api.skynyx.dev/v1/add_water_mark_to_pdf" -H "apiKey: your_default_api_key" -F "pdf_file=@/c/Users/YourName/Downloads/sample.pdf" -F "watermark_text=YourWatermarkText" -o result.jsoncurl -X POST https://api.skynyx.dev/v1/add_water_mark_to_pdf ^
-H "apiKey: your_default_api_key" ^
-F "pdf_file=@\"C:/Users/YourName/Downloads/sample.pdf\"" ^
-F "watermark_text=YourWatermarkText" ^
-o result.jsonimport java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import okhttp3.*;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
public class Program {
public static void main(String[] args) throws IOException {
OkHttpClient client = new OkHttpClient();
File file = new File("C:/Users/YourName/Downloads/sample.pdf");
RequestBody requestBody = new MultipartBody.Builder()
.setType(MultipartBody.FORM)
.addFormDataPart("pdf_file", file.getName(),
RequestBody.create(file, MediaType.parse("application/pdf")))
.addFormDataPart("watermark_text", "YourWatermarkText")
.build();
Request request = new Request.Builder()
.url("https://api.skynyx.dev/v1/add_water_mark_to_pdf")
.addHeader("apiKey", "your_default_api_key")
.post(requestBody)
.build();
try (Response response = client.newCall(request).execute()) {
if (response.body() != null) {
String responseBody = response.body().string();
JsonObject json = JsonParser.parseString(responseBody).getAsJsonObject();
if (json.has("status") && json.get("status").getAsInt() == 200) {
try (FileOutputStream outputStream = new FileOutputStream("result.json")) {
outputStream.write(responseBody.getBytes());
}
System.out.println("Response saved to result.json");
System.out.println("Watermarked PDF URL: " + json.get("result").getAsString());
} else {
System.out.println("API returned error: " + json.toString());
}
} else {
System.out.println("Empty response from server");
}
}
}
}const fs = require('fs');
const axios = require('axios');
const FormData = require('form-data');
async function main() {
const filePath = "C:/Users/YourName/Downloads/sample.pdf";
const form = new FormData();
form.append('pdf_file', fs.createReadStream(filePath));
form.append('watermark_text', 'YourWatermarkText');
try {
const response = await axios.post(
'https://api.skynyx.dev/v1/add_water_mark_to_pdf',
form,
{
headers: {
...form.getHeaders(),
'apiKey': 'your_default_api_key',
}
}
);
const data = response.data;
if (data.status === 200) {
fs.writeFileSync('result.json', JSON.stringify(data, null, 2));
console.log('Response saved to result.json');
console.log('Watermarked PDF URL:', data.result);
} else {
console.log('API returned error:', data);
}
} catch (error) {
console.error('Request error:', error.message);
}
}
main();using System;
using System.IO;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text.Json;
using System.Threading.Tasks;
class Program
{
static async Task Main()
{
var filePath = @"C:\Users\YourName\Downloads\sample.pdf";
var apiUrl = "https://api.skynyx.dev/v1/add_water_mark_to_pdf";
using var client = new HttpClient();
using var form = new MultipartFormDataContent();
var fileBytes = File.ReadAllBytes(filePath);
var fileContent = new ByteArrayContent(fileBytes);
fileContent.Headers.ContentType = MediaTypeHeaderValue.Parse("application/pdf");
form.Add(fileContent, "pdf_file", Path.GetFileName(filePath));
form.Add(new StringContent("YourWatermarkText"), "watermark_text");
client.DefaultRequestHeaders.Add("apiKey", "your_default_api_key");
var response = await client.PostAsync(apiUrl, form);
var responseBody = await response.Content.ReadAsStringAsync();
var json = JsonSerializer.Deserialize<JsonElement>(responseBody);
if (json.GetProperty("status").GetInt32() == 200) {
await File.WriteAllTextAsync("result.json", responseBody);
Console.WriteLine("Response saved to result.json");
Console.WriteLine("Watermarked PDF URL: " + json.GetProperty("result").GetString());
} else {
Console.WriteLine("API returned error: " + responseBody);
}
}
}import requests
import json
file_path = "C:/Users/YourName/Downloads/sample.pdf"
url = "https://api.skynyx.dev/v1/add_water_mark_to_pdf"
headers = {"apiKey": "your_default_api_key"}
with open(file_path, "rb") as f:
files = {"pdf_file": (file_path.split('/')[-1], f, "application/pdf")}
data = {"watermark_text": "YourWatermarkText"}
response = requests.post(url, headers=headers, files=files, data=data)
if response.status_code == 200:
json_data = response.json()
if json_data.get("status") == 200:
with open("result.json", "w") as out_file:
json.dump(json_data, out_file, indent=2)
print("Response saved to result.json")
print("Watermarked PDF URL:", json_data.get("result"))
else:
print("API returned error:", json_data)
else:
print("HTTP request failed with status:", response.status_code)<?php
$filePath = 'C:/Users/YourName/Downloads/sample.pdf';
$url = 'https://api.skynyx.dev/v1/add_water_mark_to_pdf';
$apiKey = 'your_default_api_key';
$ch = curl_init();
$postFields = [
'pdf_file' => new CURLFile($filePath, 'application/pdf', basename($filePath)),
'watermark_text' => 'YourWatermarkText'
];
$headers = ['apiKey: ' . $apiKey];
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $postFields);
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$response = curl_exec($ch);
$httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
if ($httpCode === 200) {
$json = json_decode($response, true);
if ($json['status'] === 200) {
file_put_contents('result.json', $response);
echo "Response saved to result.json
";
echo "Watermarked PDF URL: " . $json['result'];
} else {
echo "API returned error: " . $response;
}
} else {
echo "HTTP request failed with code: $httpCode";
}
curl_close($ch);POST /v1/add_water_mark_to_pdf HTTP/1.1
Host: api.skynyx.dev
apiKey: your_default_api_key
Content-Type: multipart/form-data; boundary=----BOUNDARY
------BOUNDARY
Content-Disposition: form-data; name="pdf_file"; filename="sample.pdf"
Content-Type: application/pdf
<binary content of sample.pdf>
------BOUNDARY
Content-Disposition: form-data; name="watermark_text"
YourWatermarkText
------BOUNDARY--