What is a PNG file and when should I use it?

PNG (Portable Network Graphics) is a lossless image format that supports transparency. Use PNG for logos, icons, screenshots, and images requiring transparent backgrounds or sharp edges.

Does compressing a PNG affect its transparency?

No. PNG transparency (alpha channel) is fully preserved. Transparent pixels stay transparent, semi-transparent pixels keep their exact opacity. The compressed PNG looks identical to the original over any background.

How much can I reduce a PNG file size?

Logos and flat-color graphics reduce by 40–70%. Screenshots reduce by 40–65%. PNG photos reduce by 30–60%. For photos without transparency, converting to JPG achieves 60–90% reduction.

Is PNG compression lossless?

Traditional PNG is lossless. Our tool applies near-lossless techniques at lower quality settings for greater size reduction while keeping quality imperceptible on screen. Output is always saved as PNG with full alpha channel support.

When should I use PNG instead of JPG?

Use PNG when you need transparent backgrounds, sharp edges, logos with flat colors, or lossless quality for further editing. Use JPG for photographs without transparency — JPG compresses photos far more efficiently.

How do I compress a PNG image for a website?

Upload your PNG, set quality to 75–85 for logos or 60–70 for screenshots, then download. For even smaller files, convert the compressed PNG to WebP — WebP lossless mode is typically 26% smaller than PNG.

Can I compress PNG without losing sharp edges and text?

Yes. At quality 80 and above, logos, text, and sharp edges are preserved with no visible degradation. The algorithm is conservative on high-contrast edges and text.

Are my PNG files safe when using this tool?

Yes. All PNG compression happens in your browser using JavaScript. Files are never uploaded to any server, never stored, and never transmitted anywhere. No accounts, no watermarks, no limits.

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What Is a PNG File?

PNG (Portable Network Graphics) is a widely used image format designed for lossless compression — meaning every pixel in the original image is perfectly preserved in the output. PNG was created as a patent-free alternative to GIF and has become the standard format for logos, icons, screenshots, illustrations, and any image that requires transparency. Unlike JPG, which permanently removes image data during compression, PNG keeps the image data intact.

PNG supports an alpha channel — a fourth channel of image data that controls pixel transparency. This makes PNG the only choice when you need images with transparent backgrounds: product photos without a white background, logos placed over colored headers, icons with irregular shapes, and UI elements that must blend with any background color. Compressing a PNG file reduces its size without affecting the transparency or any pixel data.

PNG files come in two main variants: PNG-24 (full color, up to 16 million colors) and PNG-8 (256 colors, like a GIF but with transparency). Our compressor handles PNG-24 files, which are the standard for photographs and detailed graphics. For illustrations with flat colors, converting to PNG-8 (outside the scope of this tool) can reduce sizes further.

How to Compress PNG Online — 3 Simple Steps

1
Upload your PNG file
Click the upload area, drag and drop your PNG file, or paste from clipboard (Ctrl+V). Files up to 20MB are supported. Your PNG is never sent to any server — all processing happens locally in your browser with full privacy.
2
Set the compression level
Use the quality slider to control compression aggressiveness. For PNG files containing photographs or gradients, lower quality settings (60–75) can still produce excellent results. For PNG files with flat colors, logos, and line art, higher quality settings (85+) preserve the sharpness of edges and text.
3
Download your compressed PNG
Your compressed PNG is ready immediately. The result card shows the original size, new size, and percentage reduction. Transparency is fully preserved — download and use the file exactly as you would the original.

Does Compressing PNG Affect Transparency?

No. PNG transparency (alpha channel) is fully preserved during compression. This is one of the most important properties of PNG compression — unlike converting a PNG to JPG, which would replace transparent pixels with a solid white or black background, compressing a PNG keeps every transparent pixel exactly as it was. Logos, icons, and UI elements with irregular shapes or semi-transparent edges will look identical after compression.

If you have a PNG with a transparent background and need to place it on a webpage or design, compressing it will not affect how it blends with the surrounding content. The compressed PNG will still have the same transparent regions, the same semi-transparent edges (anti-aliasing), and the same alpha channel data as the original.

How Much Can I Compress a PNG File?

PNG compression results vary significantly depending on the content of the image:

PNG Photos and Gradients — 30–60% reduction

PNG files containing photographs or complex gradients typically reduce by 30–60%. These images have high entropy (lots of varied pixel data), which limits how much lossless compression can achieve.

Logos and Flat-Color Graphics — 40–70% reduction

PNG files with large areas of flat color, simple gradients, or limited color palettes compress very well. A logo with a transparent background can often be reduced by 50–70% with no visible change.

Screenshots — 40–65% reduction

Screenshots of websites, applications, or documents typically compress well due to flat UI colors and sharp text areas. A 1080p screenshot that starts at 2MB can often be reduced to under 800KB.

PNG vs JPG for Photos — 10–30% vs 60–90%

For photographic content without transparency, JPG will always compress more efficiently than PNG. If you don't need transparency, consider converting your PNG to JPG for much smaller file sizes.

PNG vs JPG vs WebP: Choosing the Right Format

Each image format has distinct strengths. Choosing the wrong format for your use case results in unnecessarily large files or avoidable quality loss:

PNG — Logos & Transparency

Use when you need transparency, sharp edges, or lossless quality. Ideal for logos, icons, UI elements, and screenshots. Larger file sizes for photographs.

JPG — Photos Without Transparency

Best for photographs and complex images without transparency. Smaller file sizes than PNG for photos, with excellent quality at 75–85%. No transparency support.

WebP — Best of Both

Modern format that beats both PNG and JPG. Supports transparency, 25–35% smaller than JPG, lossless mode available. Ideal for web performance. All modern browsers support it.

For web use, consider converting PNG to WebP to get smaller files while keeping transparency. WebP with lossless compression is typically 26% smaller than PNG at the same quality.

Compressing PNG Images for Websites

Unoptimized PNG files are one of the most common causes of slow-loading websites. A single uncompressed logo PNG can be 1–5MB; a compressed version of the same logo is typically 100–300KB. For websites with multiple PNG assets — hero images, product renders, UI screenshots — proper PNG compression can reduce total page weight by several megabytes, directly improving Google Core Web Vitals scores (LCP, CLS) and SEO rankings.

A best-practice workflow for web PNG images: compress with this tool first, then consider converting to WebP for even smaller files. Use PNG only when WebP is not supported by your target platform. For any PNG that does not require transparency, switching to a compressed JPG will typically achieve 50–80% further size reduction.

Privacy — Your PNG Files Never Leave Your Device

This PNG compressor operates entirely within your browser. Your PNG files are never uploaded to any server, stored in the cloud, or sent anywhere. Compression is performed locally using the browser's Canvas API and JavaScript Web Workers. Close the tab and all image data is cleared from memory permanently. There are no accounts, no watermarks, and no usage limits.

For details on data handling and advertising, see our Privacy Policy and Terms of Service.

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Frequently Asked Questions

: PNG (Portable Network Graphics) is a lossless image format that supports transparency. Use PNG for logos, icons, UI elements, screenshots, and any image that requires a transparent background or sharp edges without compression artifacts. For photographs without transparency needs, JPG or WebP will produce smaller files.
: No. PNG transparency (alpha channel) is fully preserved during compression. Transparent pixels stay transparent, semi-transparent pixels keep their exact opacity, and the alpha channel data is not modified in any way. Your compressed PNG will look identical to the original when placed over any background.
: PNG compression results vary by image content. Logos and flat-color graphics typically reduce by 40–70%. Screenshots compress by 40–65%. PNG files containing photographs reduce by 30–60%. For photos without transparency, converting to JPG instead will achieve much larger reductions (60–90%).
: Traditional PNG compression is lossless — no image data is removed. Our compressor applies near-lossless techniques at lower quality settings, which can achieve greater file size reductions while keeping quality imperceptible on screen. The output is still saved as a PNG with full alpha channel support.
: Use PNG when you need: (1) transparent backgrounds, (2) sharp edges and text without blurring, (3) logos and graphics with flat colors, (4) lossless quality for images that will be further edited. Use JPG for photographs, camera shots, and any image without transparency needs — JPG compresses photographic content far more efficiently.
: Upload your PNG using this tool, set quality to 75–85 for logos with detail or 60–70 for screenshots, then download. For further size reduction, consider converting the compressed PNG to WebP using our Convert tool — WebP with lossless mode is typically 26% smaller than PNG at the same quality, and all modern browsers support it.
: Yes. At quality settings of 80 and above, logos, text, and sharp edges are preserved with no visible degradation. The compression algorithm is most aggressive on smooth gradients and photo-like areas, and more conservative on high-contrast edges and text, which helps preserve visual sharpness.
: Yes, completely safe. All PNG compression happens entirely in your browser using JavaScript. Your files are never uploaded to any server, never stored, and never transmitted anywhere. The compression process runs offline in your browser — there is no network request for the image data. Your files are private by design.