No browser runtime to maintain
Keep ASP.NET services and background workers free of local browser binaries and browser-process lifecycle code.
HTML to PNG with C#
Generate PNG images with C#
No browser management required
Render HTML and CSS from C# without installing Chrome, running Playwright or Selenium, or building a separate image-storage pipeline.
- No browser processes to maintain
- Consistent managed Chromium rendering
- Complete C# request below
View example
Request
C# workflow
Test the render before adding it to C#
Adjust the HTML and CSS here, then use the C# example below instead of recreating the browser-rendering workflow locally.
Managed rendering
Skip the fragile parts of native C# browser automation
Keep the application code focused on the request and response while HCTI manages Chromium, render isolation, retries, and hosted output.
Predictable production rendering
Use managed browser versions, isolated render jobs, built-in timing controls, and consistent viewport behavior across deployments.
A usable image URL immediately
Receive the hosted .png result without building a separate pipeline for temporary files, uploads, storage, and delivery.
HTML to image API
Send one C# request instead of running a browser
POST the HTML, CSS, and format from C#. HCTI handles the browser lifecycle and returns the generated .png URL.
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HTML and CSS input
Send complete markup and styles, including browser-supported fonts, images, SVG, and JavaScript.
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PNG output
Set format to png and use the hosted .png URL returned by the API.
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Viewport and crop controls
Set viewport dimensions and device scale, or crop the result to a CSS selector.
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Page environment
Choose light or dark mode, timezone, and screen or print media.
Request
How it works
From markup to a finished PNG
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Send HTML and CSS
Submit the content with format set to png and any viewport or browser settings.
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Chromium renders the design
The API loads the markup, styles, fonts, and assets in a managed browser environment.
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Use the .png URL
Embed the hosted result, download the file, or save it in your own storage and application records.
Output formats
One API, the format your workflow needs
Keep the same HTML and CSS. Choose lossless detail, compact compatibility, modern web delivery, or a paginated document.
Looking to capture a webpage as PNG? Explore URL to PNG in C#Compact + universal
Modern + efficient
Document + printable
.jpeg
HTML to JPEG
Smaller files and broad compatibility for photography, previews, and content-heavy pages.
Explore JPEG.webp
HTML to WebP
Strong visual quality, transparency, and modern compression for web delivery.
Explore WebP.pdf
HTML to PDF
Paginated documents with page sizing, margins, backgrounds, and print styles.
Explore PDFExample code
Render HTML to PNG in C#
Copy a complete C# request. Authentication, HTML, CSS, viewport settings, and response handling are shown together.
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using System.Net.Http.Headers;
using System.Net.Http.Json;
using System.Collections.Generic;
using System.Text;
using System.Text.Json.Nodes;
var apiId = Environment.GetEnvironmentVariable("HCTI_API_ID")!;
var apiKey = Environment.GetEnvironmentVariable("HCTI_API_KEY")!;
using var client = new HttpClient();
var credentials = Convert.ToBase64String(Encoding.ASCII.GetBytes($"{apiId}:{apiKey}"));
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", credentials);
var request = new
{
html = """
<div class="card">
<h1>Hello, world!</h1>
<p>Generated from HTML and CSS.</p>
</div>
""",
css = """
.card {
width: 480px;
padding: 40px;
background: #f0fdf4;
color: #052e16;
font-family: sans-serif;
}
""",
format = "png",
};
using var response = await client.PostAsJsonAsync("https://hcti.io/v1/image", request);
response.EnsureSuccessStatusCode();
var result = await response.Content.ReadFromJsonAsync<JsonObject>();
var imageUrl = result?["url"]?.GetValue<string>();
if (imageUrl is not null)
{
Console.WriteLine(imageUrl);
}
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Ready to render?
Create your first PNG from HTML and CSS
Send HTML and CSS to the API and receive a hosted .png image URL without running browser infrastructure.