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Select an image to see your savings

What Is Image Compression?

Image compression reduces the file size of a picture without (or with minimal) loss of visible quality. There are two flavours: lossy compression (JPEG, WebP) discards information the eye can't easily see and produces dramatic size reductions; lossless compression (PNG, WebP-lossless) preserves every pixel exactly but achieves smaller savings. Compressed images load faster, save mobile data, fit within email attachment limits, and improve Google's Core Web Vitals scores — particularly Largest Contentful Paint (LCP).

Image Compressor Online — What This Tool Does

This free online image compressor reduces JPEG, PNG, and WebP files entirely in your browser. Drop in an image, set a target maximum file size in megabytes, and click Compress — the tool iteratively re-encodes the image until it fits under your target, then lets you download the result. Nothing uploads anywhere; all compression runs locally on your device.

How to Compress an Image

  • Drag an image onto the upload zone, or click to pick a file from your computer.
  • The original file name, dimensions, and size appear once the image loads.
  • Drag the Target size slider to set the maximum output size in MB (0.1–10 MB).
  • Click Compress. The tool iterates quality settings until the output fits under your target.
  • Compare original vs compressed side by side — both file size and visual quality.
  • Click Download to save the compressed image.
  • Click ✕ Remove to clear and try a different image.

Supported Formats

  • JPEG / JPG — best for photographs and complex images with many colours. Lossy compression gives the biggest size reductions (often 60–90%).
  • PNG — best for graphics, logos, screenshots, and images with transparency. Lossless compression preserves exact pixels but saves less space.
  • WebP — Google's modern format, typically 25–35% smaller than JPEG at equivalent quality. Supported in all modern browsers since 2020.

When Should I Compress Images?

  • Before uploading to a website — large images slow down page load and hurt Core Web Vitals scores. Aim for under 200 KB per hero image, under 100 KB for content images.
  • Before sending via email — Gmail caps attachments at 25 MB; many corporate mail servers reject anything over 5–10 MB.
  • Before uploading to social media — platforms re-compress everything. Pre-compressing to a sensible quality gives you control instead of letting their algorithms ruin your image.
  • Before printing or sharing portfolios — PDF portfolios balloon to hundreds of MB without compression.
  • For mobile-friendly sites — mobile users on cellular data benefit hugely from smaller payloads.

Compression Quality — How Much Is Too Much?

For JPEG, quality 75–85 is the sweet spot — visible compression artefacts only appear below 70. For PNG, lossless is the default; convert to JPEG or WebP if you need significant size reductions. This tool aims at a target file size, not a quality level, so it automatically picks the highest quality setting that meets your size budget. If results look blurry, your target size is too aggressive — bump it up by 0.5 MB and retry.

Tips & Tricks

  • Convert to WebP for the web — WebP delivers smaller files than JPEG at the same quality. Use our WebP Converter after compressing.
  • Resize before compressing — a 4000×3000 image scaled to 1600×1200 first compresses far better than just lowering quality. Use the Image Resizer.
  • Target 100–200 KB for web hero images, 50 KB for inline content images, 30 KB for thumbnails. These are the common Lighthouse-passing budgets.
  • Photos vs graphics — never save a screenshot as JPEG; the lossy artefacts around text are obvious. Save UI screenshots as PNG or WebP-lossless.
  • Batch via repeat — drop one image, compress, download, then drop the next. Settings persist within the session.

JPEG vs PNG vs WebP — Which to Use?

Use JPEG for photographs and any complex image without transparency — it produces the smallest files for that content. Use PNG for logos, icons, illustrations, screenshots, and anything needing a transparent background. Use WebP for the modern web when smaller size is the priority and your audience uses modern browsers. WebP supports both lossy and lossless modes plus transparency, making it the most flexible format.

Related Tools

Is My Image Sent to a Server?

No. Image compression runs entirely in your browser using the browser-image-compression library, which uses the HTML <canvas> API and Web Workers to re-encode images locally. Your files never leave your device — no upload, no server processing, no log. This is especially important for personal photos, work-confidential screenshots, or any image you do not want stored on a third-party server even briefly.