Image Converter

Convert images between PNG, JPG, WebP, and AVIF formats — with quality controls and batch conversion.

Last updated: March 25, 2026

Convert images locally in your browser. Nothing is uploaded to a server.

Drop up to 10 images here

Convert JPG, PNG, or WebP files in one pass.

Client-Side Processing

Input Data Stays on Device

Instant Local Execution

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What is Image Converter?

Different image formats serve very different technical purposes. PNG is a lossless format ideal for graphics with sharp edges, transparency, or text — but produces large files for photographs. JPG/JPEG uses lossy compression tailored for photographs, achieving dramatic file size reductions at slight quality cost. WebP is Google's modern format that offers both lossless and lossy compression, typically 25–35% smaller than JPG at equivalent visual quality, and is now supported by all modern browsers. AVIF (AV1 Image Format) is the newest format, offering even better compression than WebP at equivalent quality.

Choosing the right format has significant web performance implications. A 3MB hero image in JPG could be a 900KB WebP — a 70% reduction that dramatically speeds up page load times on mobile. Google's Core Web Vitals (specifically Largest Contentful Paint) are directly impacted by image format efficiency. This tool converts between all major web image formats with a configurable quality slider, allowing you to find the optimal balance between file size and visual quality before deploying images to production.

How to Use Image Converter

Drag and drop one or more image files into the upload area (PNG, JPG, GIF, BMP, WebP)

Select the target output format from the format selector (WebP, JPG, PNG, AVIF)

Adjust the quality slider (1–100%) — lower values produce smaller files with more compression artifacts

Preview the before/after comparison to verify quality is acceptable at your chosen level

Click "Download" to save each converted image, or "Download All as ZIP" for batch conversion

Common Use Cases

Converting all JPG photos on a website to WebP to improve Core Web Vitals LCP scores
Converting a PNG screenshot with transparency to JPG for email attachment (JPG is much smaller)
Converting a client-provided BMP or TIFF image to PNG for web-safe display
Batch converting all product images in an e-commerce catalog from JPG to WebP
Converting a GIF animation to WebP for the web (WebP supports animation at smaller file sizes)
Converting a high-resolution PNG design asset to JPG for use in a PDF document
Testing and comparing AVIF vs WebP file sizes for a specific photograph to choose the best format
Converting user-uploaded images to a standardized format before uploading them to cloud storage

Example Input and Output

File size comparison for the same photograph in different formats (at comparable visual quality):

Original image

Original: product-photo.png (5.2 MB, 3000×2000 px)
Task: Convert to web-optimized format at the same resolution

Sizes at equivalent quality

PNG (lossless):      5.2 MB  ████████████████████ 100%
JPEG (quality 85%):  1.1 MB  ████                  21%
WebP (quality 80%):  760 KB  ███                   15%  ← Recommended
AVIF (quality 70%):  480 KB  ██                    9%   ← Best compression

Client-Side Processing

All image format conversion runs locally using the browser's Canvas API. Your images — including personal photos, unreleased product images, or client assets — never leave your device.

Use the <picture> Element

When deploying converted images, use the HTML <picture> element to provide modern and legacy format alternatives: <picture><source srcset="image.avif" type="image/avif"><source srcset="image.webp" type="image/webp"><img src="image.jpg" alt="..."></picture>. Browsers pick the first format they support and ignore the rest — zero JavaScript, perfect compatibility.

Batch Workflow

For large-scale production image conversion (hundreds of images), this browser tool is perfect for one-offs and testing. For automated batch conversion of an entire image library, use sharp (Node.js), Pillow (Python), or ImageMagick. These command-line tools can be integrated into your build pipeline for automatic format optimization during deployment.

Frequently Asked Questions

Which image format should I use for my website?

For photographs and hero images: WebP is the best balance of quality, size, and browser support (Chrome, Firefox, Safari, Edge all support it). For images requiring transparency: WebP or PNG. For the absolute best compression on modern browsers: AVIF. For maximum compatibility including old browsers: JPG (photographs) or PNG (graphics with transparency). Use the <picture> element with multiple sources to serve WebP/AVIF to modern browsers and JPG/PNG as fallback.

What is the difference between lossless and lossy compression?

Lossless compression (PNG, WebP lossless, GIF) preserves every pixel exactly — the decompressed image is bit-for-bit identical to the original. File sizes are larger. Lossy compression (JPG, WebP lossy, AVIF) permanently discards some image data during compression. At high quality settings (85%+), the loss is perceptually invisible. At low quality settings, JPEG block artifacts and color banding become visible. For photographs, lossy compression at high quality is always recommended for the web.

What quality setting should I use for WebP?

For photographs: quality 75–85% provides exceptional file size reduction with imperceptible quality loss. For product images that need to look perfect: 85–90%. For thumbnails or preview images where some quality loss is acceptable: 60–75%. For graphics like logos or diagrams with sharp edges and solid colors, use WebP lossless mode instead of a lossy quality setting.

Does JPG support transparency (alpha channel)?

No. JPG format does not support transparency. All transparent areas are filled with white (or the matte color) when converting to JPG. If you need transparency (for logos on colored backgrounds, cutout images, etc.), use PNG or WebP instead. Converting a PNG with transparency to JPG will permanently replace transparent areas with solid white.

What is AVIF and should I use it?

AVIF (AV1 Image Format) is the newest image format, derived from the AV1 video codec. It provides the best compression of all current formats — typically 50% smaller than JPEG and 30% smaller than WebP at equivalent quality. Browser support: Chrome 85+, Firefox 113+, Safari 16+. Edge 121+. For maximum image optimization in modern projects, serve AVIF to supported browsers and WebP as fallback using the <picture> element.

Can I convert animated GIFs with this tool?

The tool handles static image conversion. Animated GIF frames can be extracted individually. For full animated GIF conversion to WebP animation, use ffmpeg (ffmpeg -i input.gif output.webp) or a dedicated animation converter — browser Canvas API has limitations with animated frame sequences.

How This Tool Works

Uploaded images are decoded using the browser's FileReader API and drawn onto an off-screen HTML Canvas element at full resolution. Conversion is performed using canvas.toBlob(callback, mimeType, qualityFactor) where mimeType is one of image/webp, image/jpeg, or image/png and qualityFactor is the selected quality percentage. For AVIF, the tool uses the browser's native AVIF encoding support (available in Chrome, Firefox, and Safari) via the same Canvas.toBlob() API with image/avif MIME type.

Technical Stack

HTML5 Canvas APICanvas.toBlob() APIFileReader APINative WebP/AVIF encodingClient-side only