typescript image to base64

In modern web development, it’s common to encode images as Base64 before transmitting or embedding them. Whether for embedding small icons in CSS/HTML, sending images via JSON APIs, or processing images entirely client‑side, you’ll often find yourself converting images to Base64 and vice versa. On the Toolexe site, their Base64 to Image converter provides a convenient browser‑based way to decode Base64 strings back into images.
Why convert an image to Base64?
Before diving into code, let’s briefly review why and when you might want to convert images to Base64:
Embedding in HTML / CSS: Using data:image/png;base64,... URIs lets you embed small images directly in markup or styles without extra HTTP requests.
APIs / Data transfer: Some APIs accept or return images encoded as Base64 strings in JSON.
Offline / client‑only workflows: In pure front-end apps or PWA contexts, you may use Base64 representations for local storage, previews, or caching.
Converting image → Base64 in TypeScript / JavaScript
Depending on environment (browser vs. Node.js or server-side), the approach differs.
In the Browser (client-side)
In a browser (or front-end TypeScript app), the usual pattern is:
User selects or uploads an image (via <input type="file"> or drag/drop).
Use a FileReader to read the image file as a data URI (i.e. Base64).
Use or transmit the resulting string.
Here is a sample TypeScript snippet:
function fileToBase64(file: File): Promise<string> {
return new Promise((resolve, reject) => {
const reader = new FileReader();
reader.onload = () => {
// reader.result is a string like "data:image/png;base64,...."
resolve(reader.result as string);
};
reader.onerror = (err) => reject(err);
reader.readAsDataURL(file);
});
}
// Usage, e.g. in an <input> change handler
const inputEl = document.getElementById('imgInput') as HTMLInputElement;
inputEl.addEventListener('change', (ev) => {
const file = (ev.target as HTMLInputElement).files?.[0];
if (file) {
fileToBase64(file).then((base64) => {
console.log('Base64 image:', base64);
// You can now set an <img> src to this, or send it over API.
});
}
});
Also, when using image-to-base64 NPM packages (or similar), there are TypeScript definitions available. For instance, @types/image-to-base64 gives you types for its APIs. When you use libraries, always check their type definitions and promise return types, so your TypeScript code remains safe and maintainable.
Integrating with tools like Toolexe’s Base64 ⇄ Image
The Toolexe site you linked provides a typescript image to base64 converter: you paste in a Base64 string (with or without the data:image/... prefix), and the tool instantly previews the decoded image.
While that is a client-side decoding tool, the same principles apply in your own TypeScript apps:
After converting an image to Base64 (with the methods above), you can display it by setting an <img src="data:image/..."> or creating a Blob and object URL.
To reverse (Base64 → image file), you parse the Base64 string (strip the prefix), convert to binary or Blob, then use URL.createObjectURL or File APIs to convert that to an image.
By combining your TypeScript encoder/decoder logic with external tools like Toolexe for debugging and preview, you can validate your conversions and troubleshoot issues.
Summary
Converting images to Base64 in TypeScript is a common need for embedding, API transport, offline handling, and client-side workflows.
In browser-based TypeScript, FileReader.readAsDataURL or canvas methods help you convert files or images to Base64.
In Node.js / server-side TypeScript, fetch or fs + Buffer conversions are standard.
TypeScript’s typing (and optional opaque types) can help document or enforce correct usage of Base64 strings.
Tools like Toolexe’s Base64 ⇄ Image converter are useful for debugging, previewing, and validating your Base64 strings.