Use Nutrient DWS Processor API to render HTML pages and CSS templates into image output including PNG, JPG, TIFF, and WebP. Start a free trial, test with Postman, and move to production with credit-based pricing.
This example will convert your HTML file to a high-quality JPG image.
Try it out in three steps
index.html to your project folder.result.jpg to see the output.curl -X POST https://api.nutrient.io/build \ -H "Authorization: Bearer your_api_key_here" \ -o image.jpg \ --fail \ -F document=@index.html \ -F instructions='{ "parts": [ { "html": "document" } ], "output": { "type": "image", "format": "jpg", "dpi": 500 } }'curl -X POST https://api.nutrient.io/build ^ -H "Authorization: Bearer your_api_key_here" ^ -o image.jpg ^ --fail ^ -F document=@index.html ^ -F instructions="{\"parts\": [{\"html\": \"document\"}], \"output\": {\"type\": \"image\", \"format\": \"jpg\", \"dpi\": 500}}"package com.example.pspdfkit;
import java.io.File;import java.io.IOException;import java.nio.file.FileSystems;import java.nio.file.Files;import java.nio.file.StandardCopyOption;
import org.json.JSONArray;import org.json.JSONObject;
import okhttp3.MediaType;import okhttp3.MultipartBody;import okhttp3.OkHttpClient;import okhttp3.Request;import okhttp3.RequestBody;import okhttp3.Response;
public final class PspdfkitApiExample { public static void main(final String[] args) throws IOException { final RequestBody body = new MultipartBody.Builder() .setType(MultipartBody.FORM) .addFormDataPart( "document", "index.html", RequestBody.create( MediaType.parse("text/html"), new File("index.html") ) ) .addFormDataPart( "instructions", new JSONObject() .put("parts", new JSONArray() .put(new JSONObject() .put("html", "document") ) ) .put("output", new JSONObject() .put("type", "image") .put("format", "jpg") .put("dpi", 500) ).toString() ) .build();
final Request request = new Request.Builder() .url("https://api.nutrient.io/build") .method("POST", body) .addHeader("Authorization", "Bearer your_api_key_here") .build();
final OkHttpClient client = new OkHttpClient() .newBuilder() .build();
final Response response = client.newCall(request).execute();
if (response.isSuccessful()) { Files.copy( response.body().byteStream(), FileSystems.getDefault().getPath("image.jpg"), StandardCopyOption.REPLACE_EXISTING ); } else { // Handle the error throw new IOException(response.body().string()); } }}using System;using System.IO;using System.Net;using RestSharp;
namespace PspdfkitApiDemo{ class Program { static void Main(string[] args) { var client = new RestClient("https://api.nutrient.io/build");
var request = new RestRequest(Method.POST) .AddHeader("Authorization", "Bearer your_api_key_here") .AddFile("document", "index.html") .AddParameter("instructions", new JsonObject { ["parts"] = new JsonArray { new JsonObject { ["html"] = "document" } }, ["output"] = new JsonObject { ["type"] = "image", ["format"] = "jpg", ["dpi"] = 500 } }.ToString());
request.AdvancedResponseWriter = (responseStream, response) => { if (response.StatusCode == HttpStatusCode.OK) { using (responseStream) { using var outputFileWriter = File.OpenWrite("image.jpg"); responseStream.CopyTo(outputFileWriter); } } else { var responseStreamReader = new StreamReader(responseStream); Console.Write(responseStreamReader.ReadToEnd()); } };
client.Execute(request); } }}// This code requires Node.js. Do not run this code directly in a web browser.
const axios = require('axios')const FormData = require('form-data')const fs = require('fs')
const formData = new FormData()formData.append('instructions', JSON.stringify({ parts: [ { html: "document" } ], output: { type: "image", format: "jpg", dpi: 500 }}))formData.append('document', fs.createReadStream('index.html'))
;(async () => { try { const response = await axios.post('https://api.nutrient.io/build', formData, { headers: formData.getHeaders({ 'Authorization': 'Bearer your_api_key_here' }), responseType: "stream" })
response.data.pipe(fs.createWriteStream("image.jpg")) } catch (e) { const errorString = await streamToString(e.response.data) console.log(errorString) }})()
function streamToString(stream) { const chunks = [] return new Promise((resolve, reject) => { stream.on("data", (chunk) => chunks.push(Buffer.from(chunk))) stream.on("error", (err) => reject(err)) stream.on("end", () => resolve(Buffer.concat(chunks).toString("utf8"))) })}import requestsimport json
response = requests.request( 'POST', 'https://api.nutrient.io/build', headers = { 'Authorization': 'Bearer your_api_key_here' }, files = { 'document': open('index.html', 'rb') }, data = { 'instructions': json.dumps({ 'parts': [ { 'html': 'document' } ], 'output': { 'type': 'image', 'format': 'jpg', 'dpi': 500 } }) }, stream = True)
if response.ok: with open('image.jpg', 'wb') as fd: for chunk in response.iter_content(chunk_size=8096): fd.write(chunk)else: print(response.text) exit()<?php
$FileHandle = fopen('image.jpg', 'w+');
$curl = curl_init();
curl_setopt_array($curl, array( CURLOPT_URL => 'https://api.nutrient.io/build', CURLOPT_CUSTOMREQUEST => 'POST', CURLOPT_RETURNTRANSFER => true, CURLOPT_ENCODING => '', CURLOPT_POSTFIELDS => array( 'instructions' => '{ "parts": [ { "html": "document" } ], "output": { "type": "image", "format": "jpg", "dpi": 500 } }', 'document' => new CURLFILE('index.html') ), CURLOPT_HTTPHEADER => array( 'Authorization: Bearer your_api_key_here' ), CURLOPT_FILE => $FileHandle,));
$response = curl_exec($curl);
curl_close($curl);
fclose($FileHandle);POST https://api.nutrient.io/build HTTP/1.1Content-Type: multipart/form-data; boundary=--customboundaryAuthorization: Bearer your_api_key_here
--customboundaryContent-Disposition: form-data; name="instructions"Content-Type: application/json
{ "parts": [ { "html": "document" } ], "output": { "type": "image", "format": "jpg", "dpi": 500 }}--customboundaryContent-Disposition: form-data; name="document"; filename="index.html"Content-Type: text/html
(document data)--customboundary--This example will convert your HTML file to a high-quality PNG image.
Try it out in three steps
index.html to your project folder.result.png to see the output.curl -X POST https://api.nutrient.io/build \ -H "Authorization: Bearer your_api_key_here" \ -o image.png \ --fail \ -F document=@index.html \ -F instructions='{ "parts": [ { "html": "document" } ], "output": { "type": "image", "format": "png", "dpi": 500 } }'curl -X POST https://api.nutrient.io/build ^ -H "Authorization: Bearer your_api_key_here" ^ -o image.png ^ --fail ^ -F document=@index.html ^ -F instructions="{\"parts\": [{\"html\": \"document\"}], \"output\": {\"type\": \"image\", \"format\": \"png\", \"dpi\": 500}}"package com.example.pspdfkit;
import java.io.File;import java.io.IOException;import java.nio.file.FileSystems;import java.nio.file.Files;import java.nio.file.StandardCopyOption;
import org.json.JSONArray;import org.json.JSONObject;
import okhttp3.MediaType;import okhttp3.MultipartBody;import okhttp3.OkHttpClient;import okhttp3.Request;import okhttp3.RequestBody;import okhttp3.Response;
public final class PspdfkitApiExample { public static void main(final String[] args) throws IOException { final RequestBody body = new MultipartBody.Builder() .setType(MultipartBody.FORM) .addFormDataPart( "document", "index.html", RequestBody.create( MediaType.parse("text/html"), new File("index.html") ) ) .addFormDataPart( "instructions", new JSONObject() .put("parts", new JSONArray() .put(new JSONObject() .put("html", "document") ) ) .put("output", new JSONObject() .put("type", "image") .put("format", "png") .put("dpi", 500) ).toString() ) .build();
final Request request = new Request.Builder() .url("https://api.nutrient.io/build") .method("POST", body) .addHeader("Authorization", "Bearer your_api_key_here") .build();
final OkHttpClient client = new OkHttpClient() .newBuilder() .build();
final Response response = client.newCall(request).execute();
if (response.isSuccessful()) { Files.copy( response.body().byteStream(), FileSystems.getDefault().getPath("image.png"), StandardCopyOption.REPLACE_EXISTING ); } else { // Handle the error throw new IOException(response.body().string()); } }}using System;using System.IO;using System.Net;using RestSharp;
namespace PspdfkitApiDemo{ class Program { static void Main(string[] args) { var client = new RestClient("https://api.nutrient.io/build");
var request = new RestRequest(Method.POST) .AddHeader("Authorization", "Bearer your_api_key_here") .AddFile("document", "index.html") .AddParameter("instructions", new JsonObject { ["parts"] = new JsonArray { new JsonObject { ["html"] = "document" } }, ["output"] = new JsonObject { ["type"] = "image", ["format"] = "png", ["dpi"] = 500 } }.ToString());
request.AdvancedResponseWriter = (responseStream, response) => { if (response.StatusCode == HttpStatusCode.OK) { using (responseStream) { using var outputFileWriter = File.OpenWrite("image.png"); responseStream.CopyTo(outputFileWriter); } } else { var responseStreamReader = new StreamReader(responseStream); Console.Write(responseStreamReader.ReadToEnd()); } };
client.Execute(request); } }}// This code requires Node.js. Do not run this code directly in a web browser.
const axios = require('axios')const FormData = require('form-data')const fs = require('fs')
const formData = new FormData()formData.append('instructions', JSON.stringify({ parts: [ { html: "document" } ], output: { type: "image", format: "png", dpi: 500 }}))formData.append('document', fs.createReadStream('index.html'))
;(async () => { try { const response = await axios.post('https://api.nutrient.io/build', formData, { headers: formData.getHeaders({ 'Authorization': 'Bearer your_api_key_here' }), responseType: "stream" })
response.data.pipe(fs.createWriteStream("image.png")) } catch (e) { const errorString = await streamToString(e.response.data) console.log(errorString) }})()
function streamToString(stream) { const chunks = [] return new Promise((resolve, reject) => { stream.on("data", (chunk) => chunks.push(Buffer.from(chunk))) stream.on("error", (err) => reject(err)) stream.on("end", () => resolve(Buffer.concat(chunks).toString("utf8"))) })}import requestsimport json
response = requests.request( 'POST', 'https://api.nutrient.io/build', headers = { 'Authorization': 'Bearer your_api_key_here' }, files = { 'document': open('index.html', 'rb') }, data = { 'instructions': json.dumps({ 'parts': [ { 'html': 'document' } ], 'output': { 'type': 'image', 'format': 'png', 'dpi': 500 } }) }, stream = True)
if response.ok: with open('image.png', 'wb') as fd: for chunk in response.iter_content(chunk_size=8096): fd.write(chunk)else: print(response.text) exit()<?php
$FileHandle = fopen('image.png', 'w+');
$curl = curl_init();
curl_setopt_array($curl, array( CURLOPT_URL => 'https://api.nutrient.io/build', CURLOPT_CUSTOMREQUEST => 'POST', CURLOPT_RETURNTRANSFER => true, CURLOPT_ENCODING => '', CURLOPT_POSTFIELDS => array( 'instructions' => '{ "parts": [ { "html": "document" } ], "output": { "type": "image", "format": "png", "dpi": 500 } }', 'document' => new CURLFILE('index.html') ), CURLOPT_HTTPHEADER => array( 'Authorization: Bearer your_api_key_here' ), CURLOPT_FILE => $FileHandle,));
$response = curl_exec($curl);
curl_close($curl);
fclose($FileHandle);POST https://api.nutrient.io/build HTTP/1.1Content-Type: multipart/form-data; boundary=--customboundaryAuthorization: Bearer your_api_key_here
--customboundaryContent-Disposition: form-data; name="instructions"Content-Type: application/json
{ "parts": [ { "html": "document" } ], "output": { "type": "image", "format": "png", "dpi": 500 }}--customboundaryContent-Disposition: form-data; name="document"; filename="index.html"Content-Type: text/html
(document data)--customboundary--This example will convert your HTML file to a TIFF image.
Try it out in three steps
index.html to your project folder.result.tiff to see the output.curl -X POST https://api.nutrient.io/build \ -H "Authorization: Bearer your_api_key_here" \ -o image.tiff \ --fail \ -F document=@index.html \ -F instructions='{ "parts": [ { "html": "document" } ], "output": { "type": "image", "format": "tiff", "dpi": 100 } }'curl -X POST https://api.nutrient.io/build ^ -H "Authorization: Bearer your_api_key_here" ^ -o image.tiff ^ --fail ^ -F document=@index.html ^ -F instructions="{\"parts\": [{\"html\": \"document\"}], \"output\": {\"type\": \"image\", \"format\": \"tiff\", \"dpi\": 100}}"package com.example.pspdfkit;
import java.io.File;import java.io.IOException;import java.nio.file.FileSystems;import java.nio.file.Files;import java.nio.file.StandardCopyOption;
import org.json.JSONArray;import org.json.JSONObject;
import okhttp3.MediaType;import okhttp3.MultipartBody;import okhttp3.OkHttpClient;import okhttp3.Request;import okhttp3.RequestBody;import okhttp3.Response;
public final class PspdfkitApiExample { public static void main(final String[] args) throws IOException { final RequestBody body = new MultipartBody.Builder() .setType(MultipartBody.FORM) .addFormDataPart( "document", "index.html", RequestBody.create( MediaType.parse("text/html"), new File("index.html") ) ) .addFormDataPart( "instructions", new JSONObject() .put("parts", new JSONArray() .put(new JSONObject() .put("html", "document") ) ) .put("output", new JSONObject() .put("type", "image") .put("format", "tiff") .put("dpi", 100) ).toString() ) .build();
final Request request = new Request.Builder() .url("https://api.nutrient.io/build") .method("POST", body) .addHeader("Authorization", "Bearer your_api_key_here") .build();
final OkHttpClient client = new OkHttpClient() .newBuilder() .build();
final Response response = client.newCall(request).execute();
if (response.isSuccessful()) { Files.copy( response.body().byteStream(), FileSystems.getDefault().getPath("image.tiff"), StandardCopyOption.REPLACE_EXISTING ); } else { // Handle the error throw new IOException(response.body().string()); } }}using System;using System.IO;using System.Net;using RestSharp;
namespace PspdfkitApiDemo{ class Program { static void Main(string[] args) { var client = new RestClient("https://api.nutrient.io/build");
var request = new RestRequest(Method.POST) .AddHeader("Authorization", "Bearer your_api_key_here") .AddFile("document", "index.html") .AddParameter("instructions", new JsonObject { ["parts"] = new JsonArray { new JsonObject { ["html"] = "document" } }, ["output"] = new JsonObject { ["type"] = "image", ["format"] = "tiff", ["dpi"] = 100 } }.ToString());
request.AdvancedResponseWriter = (responseStream, response) => { if (response.StatusCode == HttpStatusCode.OK) { using (responseStream) { using var outputFileWriter = File.OpenWrite("image.tiff"); responseStream.CopyTo(outputFileWriter); } } else { var responseStreamReader = new StreamReader(responseStream); Console.Write(responseStreamReader.ReadToEnd()); } };
client.Execute(request); } }}// This code requires Node.js. Do not run this code directly in a web browser.
const axios = require('axios')const FormData = require('form-data')const fs = require('fs')
const formData = new FormData()formData.append('instructions', JSON.stringify({ parts: [ { html: "document" } ], output: { type: "image", format: "tiff", dpi: 100 }}))formData.append('document', fs.createReadStream('index.html'))
;(async () => { try { const response = await axios.post('https://api.nutrient.io/build', formData, { headers: formData.getHeaders({ 'Authorization': 'Bearer your_api_key_here' }), responseType: "stream" })
response.data.pipe(fs.createWriteStream("image.tiff")) } catch (e) { const errorString = await streamToString(e.response.data) console.log(errorString) }})()
function streamToString(stream) { const chunks = [] return new Promise((resolve, reject) => { stream.on("data", (chunk) => chunks.push(Buffer.from(chunk))) stream.on("error", (err) => reject(err)) stream.on("end", () => resolve(Buffer.concat(chunks).toString("utf8"))) })}import requestsimport json
response = requests.request( 'POST', 'https://api.nutrient.io/build', headers = { 'Authorization': 'Bearer your_api_key_here' }, files = { 'document': open('index.html', 'rb') }, data = { 'instructions': json.dumps({ 'parts': [ { 'html': 'document' } ], 'output': { 'type': 'image', 'format': 'tiff', 'dpi': 100 } }) }, stream = True)
if response.ok: with open('image.tiff', 'wb') as fd: for chunk in response.iter_content(chunk_size=8096): fd.write(chunk)else: print(response.text) exit()<?php
$FileHandle = fopen('image.tiff', 'w+');
$curl = curl_init();
curl_setopt_array($curl, array( CURLOPT_URL => 'https://api.nutrient.io/build', CURLOPT_CUSTOMREQUEST => 'POST', CURLOPT_RETURNTRANSFER => true, CURLOPT_ENCODING => '', CURLOPT_POSTFIELDS => array( 'instructions' => '{ "parts": [ { "html": "document" } ], "output": { "type": "image", "format": "tiff", "dpi": 100 } }', 'document' => new CURLFILE('index.html') ), CURLOPT_HTTPHEADER => array( 'Authorization: Bearer your_api_key_here' ), CURLOPT_FILE => $FileHandle,));
$response = curl_exec($curl);
curl_close($curl);
fclose($FileHandle);POST https://api.nutrient.io/build HTTP/1.1Content-Type: multipart/form-data; boundary=--customboundaryAuthorization: Bearer your_api_key_here
--customboundaryContent-Disposition: form-data; name="instructions"Content-Type: application/json
{ "parts": [ { "html": "document" } ], "output": { "type": "image", "format": "tiff", "dpi": 100 }}--customboundaryContent-Disposition: form-data; name="document"; filename="index.html"Content-Type: text/html
(document data)--customboundary--This example will convert your HTML file to a WebP image.
Try it out in three steps
index.html to your project folder.result.webp to see the output.curl -X POST https://api.nutrient.io/build \ -H "Authorization: Bearer your_api_key_here" \ -o image.webp \ --fail \ -F document=@index.html \ -F instructions='{ "parts": [ { "html": "document" } ], "output": { "type": "image", "format": "webp", "dpi": 500 } }'curl -X POST https://api.nutrient.io/build ^ -H "Authorization: Bearer your_api_key_here" ^ -o image.webp ^ --fail ^ -F document=@index.html ^ -F instructions="{\"parts\": [{\"html\": \"document\"}], \"output\": {\"type\": \"image\", \"format\": \"webp\", \"dpi\": 500}}"package com.example.pspdfkit;
import java.io.File;import java.io.IOException;import java.nio.file.FileSystems;import java.nio.file.Files;import java.nio.file.StandardCopyOption;
import org.json.JSONArray;import org.json.JSONObject;
import okhttp3.MediaType;import okhttp3.MultipartBody;import okhttp3.OkHttpClient;import okhttp3.Request;import okhttp3.RequestBody;import okhttp3.Response;
public final class PspdfkitApiExample { public static void main(final String[] args) throws IOException { final RequestBody body = new MultipartBody.Builder() .setType(MultipartBody.FORM) .addFormDataPart( "document", "index.html", RequestBody.create( MediaType.parse("text/html"), new File("index.html") ) ) .addFormDataPart( "instructions", new JSONObject() .put("parts", new JSONArray() .put(new JSONObject() .put("html", "document") ) ) .put("output", new JSONObject() .put("type", "image") .put("format", "webp") .put("dpi", 500) ).toString() ) .build();
final Request request = new Request.Builder() .url("https://api.nutrient.io/build") .method("POST", body) .addHeader("Authorization", "Bearer your_api_key_here") .build();
final OkHttpClient client = new OkHttpClient() .newBuilder() .build();
final Response response = client.newCall(request).execute();
if (response.isSuccessful()) { Files.copy( response.body().byteStream(), FileSystems.getDefault().getPath("image.webp"), StandardCopyOption.REPLACE_EXISTING ); } else { // Handle the error throw new IOException(response.body().string()); } }}using System;using System.IO;using System.Net;using RestSharp;
namespace PspdfkitApiDemo{ class Program { static void Main(string[] args) { var client = new RestClient("https://api.nutrient.io/build");
var request = new RestRequest(Method.POST) .AddHeader("Authorization", "Bearer your_api_key_here") .AddFile("document", "index.html") .AddParameter("instructions", new JsonObject { ["parts"] = new JsonArray { new JsonObject { ["html"] = "document" } }, ["output"] = new JsonObject { ["type"] = "image", ["format"] = "webp", ["dpi"] = 500 } }.ToString());
request.AdvancedResponseWriter = (responseStream, response) => { if (response.StatusCode == HttpStatusCode.OK) { using (responseStream) { using var outputFileWriter = File.OpenWrite("image.webp"); responseStream.CopyTo(outputFileWriter); } } else { var responseStreamReader = new StreamReader(responseStream); Console.Write(responseStreamReader.ReadToEnd()); } };
client.Execute(request); } }}// This code requires Node.js. Do not run this code directly in a web browser.
const axios = require('axios')const FormData = require('form-data')const fs = require('fs')
const formData = new FormData()formData.append('instructions', JSON.stringify({ parts: [ { html: "document" } ], output: { type: "image", format: "webp", dpi: 500 }}))formData.append('document', fs.createReadStream('index.html'))
;(async () => { try { const response = await axios.post('https://api.nutrient.io/build', formData, { headers: formData.getHeaders({ 'Authorization': 'Bearer your_api_key_here' }), responseType: "stream" })
response.data.pipe(fs.createWriteStream("image.webp")) } catch (e) { const errorString = await streamToString(e.response.data) console.log(errorString) }})()
function streamToString(stream) { const chunks = [] return new Promise((resolve, reject) => { stream.on("data", (chunk) => chunks.push(Buffer.from(chunk))) stream.on("error", (err) => reject(err)) stream.on("end", () => resolve(Buffer.concat(chunks).toString("utf8"))) })}import requestsimport json
response = requests.request( 'POST', 'https://api.nutrient.io/build', headers = { 'Authorization': 'Bearer your_api_key_here' }, files = { 'document': open('index.html', 'rb') }, data = { 'instructions': json.dumps({ 'parts': [ { 'html': 'document' } ], 'output': { 'type': 'image', 'format': 'webp', 'dpi': 500 } }) }, stream = True)
if response.ok: with open('image.webp', 'wb') as fd: for chunk in response.iter_content(chunk_size=8096): fd.write(chunk)else: print(response.text) exit()<?php
$FileHandle = fopen('image.webp', 'w+');
$curl = curl_init();
curl_setopt_array($curl, array( CURLOPT_URL => 'https://api.nutrient.io/build', CURLOPT_CUSTOMREQUEST => 'POST', CURLOPT_RETURNTRANSFER => true, CURLOPT_ENCODING => '', CURLOPT_POSTFIELDS => array( 'instructions' => '{ "parts": [ { "html": "document" } ], "output": { "type": "image", "format": "webp", "dpi": 500 } }', 'document' => new CURLFILE('index.html') ), CURLOPT_HTTPHEADER => array( 'Authorization: Bearer your_api_key_here' ), CURLOPT_FILE => $FileHandle,));
$response = curl_exec($curl);
curl_close($curl);
fclose($FileHandle);POST https://api.nutrient.io/build HTTP/1.1Content-Type: multipart/form-data; boundary=--customboundaryAuthorization: Bearer your_api_key_here
--customboundaryContent-Disposition: form-data; name="instructions"Content-Type: application/json
{ "parts": [ { "html": "document" } ], "output": { "type": "image", "format": "webp", "dpi": 500 }}--customboundaryContent-Disposition: form-data; name="document"; filename="index.html"Content-Type: text/html
(document data)--customboundary--Render HTML, CSS, fonts, and assets into pixel-perfect image output including PNG, JPG, TIFF, and WebP for thumbnails, previews, and sharing workflows.
Use REST, Postman, curl, JavaScript, Python, Java, C#, PHP, or HTTP to automate HTML-to-image rendering inside larger document-processing pipelines.
HTML-to-image is one action in the DWS Processor API. Combine it with HTML-to-PDF, Office-to-image, and PDF-to-image conversion in a single request.
Most common next steps
Continue to HTML-to-PDF if the output should be PDF rather than an image, getting started for API key setup, the Postman collection for the fastest first request, Processor API pricing for credits, or the Processor API overview for broader DWS evaluation.