File conversion example using NodeJS
The ConvertAPI Node.js library offers a comprehensive solution for integrating high-quality document conversion and manipulation directly into your Node.js applications and services.
Whether you need to transform PDFs into Office files, merge multiple documents, extract text from images, or handle other format conversions, the library covers a broad range of use cases and file types.
By leveraging Node.js’s asynchronous model, it lets you process documents in a highly scalable, non-blocking manner—ideal for modern, cloud-based architectures.
Combined with Node.js’s event-driven architecture, the library helps you build fast, scalable, and secure document workflows that adapt to your evolving business needs.
Install the ConvertAPI NodeJS library into your project
To get started, install the ConvertAPI NodeJS SDK. Run this line from console:
npm install convertapi --save
Convert a webpage to PDF using NodeJS
The WEB to PDF conversion lets you effortlessly transform entire web pages or HTML content into high-quality PDF files.
Whether you’re capturing dynamic, user-generated pages or automating batch exports of reports, the library seamlessly turns live content into shareable, print-ready PDFs.
By allowing you to specify parameters such as page size, orientation, and output quality, you can tailor the final document to match your exact requirements.
This streamlined approach makes it simple to generate visually consistent PDFs—perfect for archiving, distribution, or documentation within your Node.js applications.
Let's see how easy it is to perform a WEB to PDF conversion in a NodeJS application:
Convert a Stream
The ConvertAPI NodeJS library supports converting files from streams.
This makes it easy to integrate document conversion into your existing Node.js applications, allowing you to process files without the need to store them on disk.
Key Features:
-
Reads input data from a stream.
-
Processes the conversion entirely in memory.
-
Outputs the result to another stream.
var fs = require('fs');
// set your api token
var convertapi = require('../lib')(process.env.CONVERT_API_TOKEN);
// Example of using readable stream to convert to pdf
// https://www.convertapi.com/docx-to-pdf
var dir = require('os').tmpdir();
// get readble stream (could be any readable stream)
var stream = fs.createReadStream('./examples/files/test.docx');
// Upload stream to the API. When uploading stream, file name must be provided.
var uploadResult = convertapi.upload(stream, 'test.docx');
convertapi.convert('pdf', { File: uploadResult })
.then(function(result) {
return result.saveFiles(dir);
})
.then(function(files) {
console.log("The PDF saved to\n" + files);
})
.catch(function(e) {
console.error(e.toString());
});
Get result file stream
The ConvertAPI NodeJS library supports getting result file stream.
This makes it easy to integrate document conversion into your existing Node.js applications, allowing for flexible handling of the output data.
Key Features:
-
Retrieves the result of a conversion as a stream.
-
Enables direct piping of the output to other processes or storage systems.
// set your api token
var convertapi = require('../lib')(process.env.CONVERT_API_TOKEN);
// Example of converting Web Page URL to PDF and reading file data as string
// https://www.convertapi.com/web-to-pdf
var fromFormat = 'web';
var conversionTimeout = 180;
var https = require('https');
var Stream = require('stream').Transform;
var params = {
Url: 'https://en.wikipedia.org/wiki/Data_conversion',
FileName: 'web-example'
};
convertapi.convert('pdf', params, fromFormat, conversionTimeout)
.then(function(result) {
result.files.forEach(function(resultFile) {
console.log("Result url: " + resultFile.url);
https.get(resultFile.url, function(response) {
var stream = new Stream();
response.on('data', function(chunk) {
stream.push(chunk);
});
response.on('end', function() {
var data = stream.read()
console.log("Downloaded data size: " + data.length);
});
});
});
})
.catch(function(e) {
console.error(e.toString());
});
Convert Base64 Content
The ConvertAPI NodeJS library supports converting Base64 content.
This example shows how to convert base64-encoded content into another format, facilitating the handling of data received in base64 encoding.
Key Features:
-
Accepts base64-encoded input data.
-
Processes the conversion to the desired format.
-
Outputs the result as a file or stream.
// set your api token
var convertapi = require('../lib')(process.env.CONVERT_API_TOKEN);
// Example of using buffer and stream to convert base64 encoded content to pdf
// https://www.convertapi.com/png-to-pdf
var dir = require('os').tmpdir();
var Readable = require('stream').Readable;
var base64Content = "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";
// get buffer from base64 string
var buffer = Buffer.from(base64Content, 'base64');
// get readble stream from buffer
var stream = new Readable()
stream.push(buffer);
stream.push(null);
// Upload stream to the API. When uploading stream, file name must be provided.
var uploadResult = convertapi.upload(stream, 'test.png');
convertapi.convert('pdf', { File: uploadResult })
.then(function(result) {
return result.saveFiles(dir);
})
.then(function(files) {
console.log("The PDF saved to\n" + files);
})
.catch(function(e) {
console.error(e.toString());
});
Conversion Workflows
The ConvertAPI NodeJS library supports conversion workflows.
This makes it easy to integrate document conversion into your existing Node.js applications, allowing you to apply multiple, step-by-step transformations to the same document.
Key Features:
-
Performs sequential conversions using intermediate results.
-
Manages multiple steps within a single process.
-
Outputs the final converted file after all transformations.
// set your api token
var convertapi = require('../lib')(process.env.CONVERT_API_TOKEN);
// Short example of conversions chaining, the PDF pages extracted and saved as separated JPGs and then ZIP'ed
// https://www.convertapi.com/doc/chaining
var dir = require('os').tmpdir();
console.log("Converting PDF to JPG and compressing result files with ZIP\n");
convertapi.convert('jpg', { File: './examples/files/test.pdf' })
.then(function(jpgResult) {
return convertapi.convert('zip', { Files: jpgResult });
})
.then(function(zipResult) {
return zipResult.saveFiles(dir);
})
.then(function(files) {
console.log("Files saved to\n" + files);
})
.catch(function(e) {
console.error(e.toString());
});
With our Node.js SDK, you can leverage a robust set of over 500+ features dedicated to document conversion and management—all from a single, streamlined toolkit.
The library effortlessly accepts documents from URLs, file streams, or local paths, ensuring a smooth fit within your existing Node.js workflows.
For even greater efficiency, consider implementing conversion workflows, which let you sequentially apply multiple transformations to the same document.
If you’re seeking detailed examples or advanced tips, don’t miss our GitHub repository, where you’ll find everything you need to get the most out of the Node.js SDK.
