Is this converter free?

Yes, WebConverter is completely free to use. There are no hidden fees, no subscription plans, and no limits on the number of files you can convert.

Do my files get uploaded to a server?

No. All conversions happen entirely in your browser using WebAssembly. Your files never leave your device, ensuring complete privacy and security.

What formats are supported?

This converter supports the following formats: BMP, DDS, GIF, HDR, ICO, JPEG, KTX, PGM, PIC, PNG, PPM, PSD, TGA, WebP.

Can I use this offline?

Yes! WebConverter works as a Progressive Web App. Once installed, you can convert files without an internet connection.

Are there file size limits?

No, there are no artificial file size limits. The only limit is your device's available memory and processing power.

How do I convert a PNG to KTX2 without toktx or the command line?

Open the KTX2 converter and drop your PNG onto the page. The file is converted to a KTX2 texture right in your browser, so you do not need to install toktx, run a command line, or upload anything. The result downloads automatically and your image never leaves your device.

Can I create a KTX2 texture in the browser with no upload?

Yes. Conversion runs entirely on your device using WebAssembly, so your image is never uploaded to a server. This works without an account, with no file-size limit, and even on a slow connection.

What is the difference between ETC1S and UASTC supercompression?

ETC1S produces the smallest files and the lowest VRAM use, which is ideal for shipping textures to cheap phones and slow networks. UASTC keeps higher quality at a larger size, which suits normal maps and detail textures. You can pick either from the Supercompress menu, or leave it off for a plain KTX2 container.

Is KTX2 supercompression with Basis free to use here?

Yes. KTX2 conversion, including Basis ETC1S and UASTC supercompression, is completely free with no sign-up, no watermark, and no limit on how many textures you convert.

Convert HDR to KTX2

Convert HDR files to KTX2 — free, private, and instant. Runs entirely in your browser, no files are uploaded.

Drop your HDR files to convert them instantly to KTX2. No uploads — everything runs in your browser. Fast, private conversion with no sign-up, no watermarks, and no file size limits. Save the planet while doing it!

Convert to

BMPDDSGIFHDRICOJPEGKTXPGMPICPNGPPMPSDTGAWebP

Drop files here or click to browse

Supported formats: BMP, DDS, GIF, HDR, ICO, JPEG, KTX, PGM, PIC, PNG, PPM, PSD, TGA, WebP

Settings

Supercompress (Basis)

Off keeps a standard uncompressed KTX2. ETC1S and UASTC produce a Basis-supercompressed KTX2 — a tiny GPU-ready texture for WebGL, three.js and game engines. Loads a small extra encoder module on first use.

Folder

Output: Same folder

You saved about 0 kg CO₂ compared to using other online converters.
No data transfer — all data stays on your device!

About the KTX2 Format

KTX2 (Khronos Texture, version 2) is a lightweight container format for GPU textures, standardised by the Khronos Group. It is designed to deliver textures efficiently to graphics APIs such as Vulkan, OpenGL, and WebGPU. KTX2 supports a wide variety of pixel formats — including compressed formats like ASTC, ETC, and BC — as well as supercompression with Zstandard or BasisLZ for minimal file sizes. The format is commonly used in game development, real-time 3D applications, and glTF assets where fast GPU upload and compact storage are critical.

Features

Near-Zero CO₂

Server-based converters upload your file, process it remotely, and send it back — consuming network and data-centre energy on every request. WebConverter runs entirely on your device, so the only energy used is your local CPU. No data transfer, no server electricity.

Install for Offline Use

WebConverter works offline as a Progressive Web App. Click "Add to Home Screen" on mobile or the install button in your browser's address bar. Once installed, you can convert files without any internet connection.