Why is there no PNG option?

PNG is a lossless format - the only way to compress it is to reduce the colour palette (8-bit PNG) or convert to a lossy format. We don't try to fake compression by re-encoding PNG; instead, send the file through image-converter (PNG → WebP or JPG) and then compress from there.

What quality is 'safe'?

75-85% is the standard 'visually lossless' band for photos. Below 70% you start to see blocky compression artefacts on smooth gradients (sky, skin). Above 90% the file barely shrinks. For UI screenshots, stay above 90% or use a lossless format instead.

Will it strip EXIF metadata?

Yes. Canvas re-encodes from raw pixels, so EXIF (camera, GPS, timestamps), the original ICC colour profile, and any embedded thumbnails are stripped. That's usually what you want when publishing to the web; if you need EXIF preserved, use a dedicated photo tool.

Bildkompressor

JPG- und WebP-Dateigrösse mit Qualitäts-Slider und Vorher/Nachher-Vorschau verkleinern.

Läuft in deinem Browser

JPG oder WebP ablegen, Qualitäts-Slider ziehen, Dateigrösse fällt sichtbar. Eine Seite-an-Seite-Vorschau zeigt den visuellen Preis der Kompression. Alles im Browser. PNG hier bewusst nicht - PNG ist verlustfrei; vorher per Bildkonverter zu WebP oder JPG umwandeln.

JPG oder WebP hier ablegen oder klicken zum Auswählen

JPG oder WebP - PNG lässt sich nicht komprimieren (vorher Bildkonverter nutzen)

So funktioniert's

Drop a JPG or WebP
Drag and drop or click to pick. PNGs are not supported here - convert first via image-converter.
Drag the quality slider
Watch the file-size readout drop and the side-by-side preview change. 75-85 is the usual sweet spot.
Download the compressed copy
Filename gets `-compressed` appended. The original is untouched.

Was ist das?

An image compressor reduces the file size of a JPG or WebP image by re-encoding the pixels at lower quality. The browser's Canvas API handles the re-encoding; you set the quality on a 0-100 scale and the encoder discards visual detail proportionally. The result is a smaller file that looks almost identical at typical viewing sizes - the workhorse trick behind every fast-loading website.

Wann verwenden

Preparing photos for a website before they slow down Core Web Vitals. Shrinking an iPhone photo from 5 MB to 200 KB before emailing it. Compressing user uploads on the way to a storage bucket where bandwidth costs add up. Anywhere file size matters and a 5-10 % visual quality drop is invisible at the viewing size.

Häufige Fehler

Compressing the same image multiple times - lossy formats lose a little quality each round (generational loss); always compress from the original. Picking 100 % quality and being disappointed by tiny savings - the sweet spot is 75-85 %. And compressing a UI screenshot to a lossy format - the compression banding around sharp edges makes the screenshot look broken.

FAQ

Why is there no PNG option?: PNG is a lossless format - the only way to compress it is to reduce the colour palette (8-bit PNG) or convert to a lossy format. We don't try to fake compression by re-encoding PNG; instead, send the file through image-converter (PNG → WebP or JPG) and then compress from there.
What quality is 'safe'?: 75-85% is the standard 'visually lossless' band for photos. Below 70% you start to see blocky compression artefacts on smooth gradients (sky, skin). Above 90% the file barely shrinks. For UI screenshots, stay above 90% or use a lossless format instead.
Will it strip EXIF metadata?: Yes. Canvas re-encodes from raw pixels, so EXIF (camera, GPS, timestamps), the original ICC colour profile, and any embedded thumbnails are stripped. That's usually what you want when publishing to the web; if you need EXIF preserved, use a dedicated photo tool.

Bildkonverter

PNG, JPG, WebP und AVIF im Browser konvertieren - kein Upload, keine Anmeldung.

Bildgrösse ändern

Bilder im Browser in Pixel oder Prozent skalieren - kein Upload.

Bild zu Base64

Bild als Data URI (Base64) konvertieren - mit kopierbaren CSS- und HTML-Snippets. Oder Data URI einfügen für Vorschau.