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Compress Image

Compress Image

Compress JPG, PNG, and WEBP images to dramatically reduce file size while keeping them looking great. It's perfect for faster websites, smaller email attachments, and saving storage — and it all happens privately in your browser.

Processed in your browser. This tool runs entirely on your device. Your image is never uploaded to us.

Overview

Our smart compression targets a file size you choose and preserves perceptual quality, so most images look identical to the original at a fraction of the weight. You see the exact before-and-after sizes and the percentage saved before you download, with no watermark added at any point.

What this tool does

The compressor analyzes your image and re-encodes it to hit a target file size while protecting the detail your eyes notice most. You set a maximum size and a quality level; the tool optimizes the image and reports the precise savings, keeping the original format intact.

Problems it solves

  • Large images are slowing down a website and hurting Core Web Vitals.
  • An email or upload form rejects files above a size limit.
  • Cloud or device storage is filling up with bulky photos.
  • You need many images small enough to load instantly on mobile.

Key benefits

  • Reduce file size by up to 80%
  • Smart compression preserves visual quality
  • See exact before/after size savings live
  • No watermarks, ever

Who it's for

Website owners and developers improving load speedBloggers and content creators publishing image-heavy postsOffice workers attaching images to emailAnyone freeing up storage on a phone or drive

How to use it

  1. 1

    Upload your image

    Drag in a JPG, PNG, or WEBP file. The tool reads the original size so you can see exactly how much you save.

  2. 2

    Set your target size

    Choose a maximum file size in megabytes. The compressor aims to land at or below it while keeping the image looking clean.

  3. 3

    Fine-tune quality

    Adjust the quality slider if you want to push the file smaller or hold onto a little extra detail.

  4. 4

    Compress and download

    Run the compression, check the before/after sizes and the percentage saved, then download your lighter image.

Example input and output

Close-up of the Compress Image page heading encoded at JPG quality 92 — the letterforms and the badge outline are clean.
Quality 92 — 26.5 KB for this crop
The same heading encoded at JPG quality 12, showing blocky halos and mosquito noise around every letter and along the badge edge.
Quality 12 — 6.3 KB, and the artifacts are obvious

Example input

A 1600 × 1000 screenshot encoded as WEBP at quality 95 — 73.4 KB.

Example output

The same image at quality 75, identical dimensions — 31.6 KB.

Dropping from quality 95 to 75 cut the file by 57% with no difference visible at normal viewing size. These are measured figures; the full quality sweep and how to reproduce it are further down this page.

What the formats actually cost: measured

One image, every format and quality setting, encoded and measured on Aug 18, 2026. The subject is a 1600 × 1000 screenshot of this site's compress image page, captured in chrome — flat colour, hard-edged text, a limited palette. WEBP does unusually well on that kind of image, so treat these as screenshot figures rather than photograph figures.

Measured file sizes for a 1600 × 1000 screenshot encoded as PNG, JPG and WEBP at a range of quality settings
FormatQualitySizevs PNG
PNGThe original capture, losslessLossless245.4 KB—
WEBPLossless mode — pixel-identical to the PNGLossless144.1 KB41% smaller
JPG95179.0 KB27% smaller
JPGThe usual recommended setting85161.5 KB34% smaller
JPG75127.1 KB48% smaller
JPGText edges start to blur6094.6 KB61% smaller
WEBP9573.4 KB70% smaller
WEBPThe usual recommended setting8544.8 KB82% smaller
WEBP7531.6 KB87% smaller

Resizing first changes more than quality does

The same screenshot resized to each width, then encoded at quality 85. Halving the width beats any quality setting you could have chosen.

Measured file sizes at three widths, each encoded as PNG, JPG and WEBP at quality 85
WidthPNGJPG q85WEBP q85
1600px245.4 KB161.5 KB44.8 KB
1200px271.8 KB99.5 KB26.0 KB
800px137.2 KB50.2 KB14.2 KB

Resizing the screenshot to 1200px made the PNG larger than the 1600px original (271.8 KB against 245.4 KB). Downscaling blends neighbouring pixels into new intermediate colours, and PNG's compression depends on long runs of repeated colour. The lossy formats show no such effect.

How to reproduce these numbers

Every figure is stat on a real encoder output. Nothing is estimated or carried over from a vendor claim.

  • sips 316 — JPG encoding (macOS built-in)
  • cwebp 1.6.0 — WEBP encoding (libwebp)
  • Chrome 151.0.7922.138 — Screenshot capture

JPG via sips -s format jpeg -s formatOptions <q>, WEBP via cwebp -q <q>. Same source, same encoders, same numbers.

JPG vs PNG vs WEBP

Not sure which format to pick? Here is how the three formats this tool supports stack up.

Comparison of the JPG, PNG, and WEBP image formats
FeatureJPGPNGWEBP
CompressionLossyLosslessLossy or lossless
TransparencyNoYes (alpha)Yes (alpha)
AnimationNoNoYes
Typical file sizeSmallLargeSmallest — about 25–35% under JPG
Best forPhotographsLogos, graphics, screenshotsAlmost anything on the web
Browser supportUniversalUniversalAll modern browsers

Short version: reach for WEBP on the web, PNG when you need transparency or crisp graphics, and JPG when you want a photo that opens everywhere.

Common use cases

Speed up your website

Compress hero images, thumbnails, and gallery photos to cut page weight and improve loading speed and search rankings.

Beat email attachment limits

Shrink images below common 10–25 MB caps so they send reliably without bouncing back.

Save storage space

Reduce the footprint of photo libraries on your phone, laptop, or cloud drive without deleting anything.

Optimize for mobile

Serve lighter images so visitors on slow or metered connections see your content load almost instantly.

Tips & best practices

  • Convert photos to WEBP before compressing

    WEBP compresses photographs more efficiently than JPG or PNG, so converting first often lets you hit a smaller target size while keeping the image looking crisp.

  • Resize oversized images first

    If an image is far larger than it will ever display, reduce its dimensions before compressing — you'll save far more than compression alone can.

  • Watch the before/after preview

    Push the quality down until you just start to notice softness, then back off a step. That sweet spot gives the smallest file with no visible loss.

Compress Image — frequently asked questions

Usually a lot, though it depends on the image and the format. In our measured test, a 1600 x 1000 PNG screenshot went from 245.4 KB to 161.5 KB as JPG at quality 85, and to 44.8 KB as WEBP — about 82% smaller. Photographs already saved as JPG have less headroom than screenshots do.

Not at sensible settings. At quality 80 to 85 the result is visually indistinguishable from the original for most images. Artifacts appear first around text and hard edges, then in flat gradients and skin tones. Below quality 60 they become obvious. The quality slider means you decide where the line sits.

Yes, though converting it is usually the bigger win. PNG is lossless, so compressing it as PNG has limited headroom. Converting the same image to WEBP typically cuts far more — and WEBP's lossless mode keeps every pixel identical while still coming out smaller. In our test that was 144.1 KB against the PNG's 245.4 KB.

Not directly — encoders take a quality setting rather than a target size. The reliable route is to resize to the dimensions you actually display, encode as WEBP at quality 85, then check the result and step the quality down in fives if it is still over budget. Switching format usually gets you there faster than lowering quality.

Yes. The compressor runs entirely in your browser, so the file is never transmitted and there is no copy on any server — not even a temporary one. That holds for screenshots containing account details, ID scans, and anything else you would not want uploaded. Check it yourself in the Network tab.

Yes. Re-encoding through a canvas drops EXIF, IPTC, and XMP data as a side effect, including the GPS coordinates that record where a photo was taken. For publishing that is a benefit on both counts — a slightly smaller file and no location data. If you need to keep or selectively edit tags, use the metadata editor instead.

Because images are usually the heaviest thing on a page and the most common cause of a slow Largest Contentful Paint, which is a Core Web Vital Google uses in ranking. Compression does not help you rank on its own — it removes a delay that was working against you.

Yes. Queue up to 20 files at a time, each up to 20 MB, and apply the same quality setting across the batch. Processing happens on your own device, so there is no upload wait, no queue, and no daily quota no matter how many batches you run.

Aim for under 200 KB for content images and under 500 KB for a large hero. Get there by resizing to the width the image actually renders at before touching quality — in our test, halving a screenshot's width from 1600px to 800px cut the file 68% with the quality setting untouched.

Sources and further reading

The claims on this page about formats, browser behaviour, and performance come from these primary sources rather than from us.

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Related reading

Formats

JPG vs PNG vs WEBP: Which Image Format Should You Use

A plain-English breakdown of when to use JPG, PNG, or WEBP — with file sizes measured from a real encode, and the mistakes that quietly bloat your site.

Read guideCompression

How to Compress Images Without Losing Quality

Compression is not just dragging a quality slider down. What actually shrinks file size, with measured numbers — and what turns your photos to mush.

Read guide

Last reviewed and updated . Written and maintained by the Appzo Tools team.