Convert Images Without Uploading — Privacy-First Browser Image Converter for PNG, JPG, WebP & AVIF

ToolBox Image Converter is a fast, browser-based tool for converting images between the most popular web formats. Whether you need to convert PNG to JPG, JPG to WebP, WebP to PNG, or any other combination of JPEG, PNG, WebP, and AVIF, this free online image converter handles it instantly — with no uploads, no sign-up, and no file size limits.

Unlike online image converters that send your files to a remote server, ToolBox Image Converter processes everything locally using the HTML5 Canvas API. Your images stay on your device, making this one of the most secure image conversion tools available. The converter supports lossy and lossless formats, a quality slider for fine-grained control, and instant side-by-side previews so you can compare before and after.

Supported Image Format Conversions

ToolBox Image Converter supports all combinations of the four most common image formats:

• JPEG (JPG): Best for photographs and complex images. Converts to WebP, PNG, and AVIF.
• PNG: Best for graphics, screenshots, and images requiring transparency. Converts to JPEG, WebP, and AVIF.
• WebP: Google's modern format with superior compression. Converts to JPEG, PNG, and AVIF.
• AVIF: The next-generation format with the best compression ratios. Converts to JPEG, PNG, and WebP.

Why Use ToolBox Image Converter?

Most image conversion tools either upload your files to a server (compromising privacy) or require software installation. ToolBox Image Converter is different:

• 100% Private: No uploads, no servers. All conversion happens in your browser.
• No File Size Limits: Convert images of any size — the limitation is your device's memory, not our tool.
• Quality Control: Fine-tune output quality with a precise slider (1-100%) for the perfect balance of size and clarity.
• Instant Preview: See your original and converted image side by side with exact file size information.
• Free Forever: No sign-up, no paywall, no credit card. Unlimited conversions.

How to Convert Images Online

Converting images with ToolBox Image is simple and takes just a few seconds:

1. Upload — Click the upload area or drag and drop an image file onto this page.
2. Select Format — Choose your target output format (JPEG, PNG, WebP, or AVIF).
3. Adjust Quality — Move the quality slider to control file size. Higher = better quality, lower = smaller file.
4. Preview — See the original and converted image side by side with file size details.
5. Download — Click download to save your converted image. Your original file is never modified.

Common Use Cases

• Convert HEIC to JPEG: iPhone and iOS devices capture photos in HEIC format. Convert them to JPEG for wider compatibility on Windows, Android, and web platforms.
• Convert PNG to JPG for websites: PNG images can be large. Converting to JPEG significantly reduces file size for faster page loads, especially for photographs.
• Convert JPG to WebP for better performance: WebP offers 25-35% smaller file sizes than JPEG at equivalent quality, making your website faster.
• Convert WebP to PNG for editing: Some image editors and design tools don't support WebP. Convert to PNG for full compatibility.