How do I compress an image to exactly 100KB?

Use a quality-slider compressor. Start at Medium quality (65%) — a typical 5MB photo drops to 300-500KB. If still too large, go to Low (40%) for 100-200KB. For precise targets under 100KB, also reduce the image dimensions — a 4000x3000 photo resized to 1200x900 at Medium quality easily hits under 100KB. The process: compress → check size → adjust quality or dimensions → re-compress.

Can I compress a PNG to a specific KB size?

PNG is a lossless format, so quality sliders do not reduce PNG file size much. The fastest way: convert PNG to JPG or WebP during compression. A 3MB PNG becomes a 200-400KB JPG at 80% quality with virtually no visible difference. If you need to keep PNG format (for transparency), reduce the image dimensions instead.

What quality setting gets my image under 200KB?

It depends on the original dimensions. For a phone photo (4000x3000 at 5-8MB): Medium quality (65%) typically gets you to 300-500KB. For under 200KB, either drop to Low (40%) or resize to 2000x1500 first. For a web screenshot (1920x1080 at 1-2MB): Medium quality alone usually gets under 200KB.

How do I compress images for email attachments?

Most email providers cap attachments at 25MB total. For a single image, compress to Medium quality (65%) — this cuts a 5MB phone photo to about 500KB. For multiple images, use Low quality (40%) or resize dimensions first. Batch compress all images at once, then attach. If sending 10+ photos, compress each to under 500KB and they will all fit within the 25MB limit.

Does compressing an image reduce quality visibly?

At High quality (85%), the difference from the original is invisible to the human eye — you save 30-50% of file size. At Medium (65%), most people cannot tell the difference on screen — you save 60-80%. At Low (40%), there is noticeable softening and some JPEG artifacts, but it is fine for thumbnails, web previews, and email attachments. The sweet spot for most uses is 65-80%.

How do I compress images for a website to load faster?

Target 50-150KB per image for web pages. Use WebP format if your site supports it — WebP is 25-35% smaller than JPG at the same quality. Resize images to the display size (do not serve a 4000px image in a 800px container). Medium quality (65%) JPG or WebP works for most web content. Use our compressor to batch process all images before uploading to your site.

What is the difference between compressing and resizing?

Compressing reduces file size by lowering image quality (discarding visual data humans cannot easily see). The dimensions stay the same. Resizing changes the pixel dimensions (e.g., 4000x3000 to 1200x900), which also reduces file size because there are fewer pixels. For maximum file size reduction, do both: resize to your target dimensions first, then compress to your target quality level.

Is the image uploaded to a server during compression?

No. The compressor runs entirely in your browser using your device processor. Your images never leave your device, are never stored on a server, and are never seen by anyone else. This matters for sensitive images — medical photos, legal documents, personal photos — where uploading to a third-party server creates privacy and compliance risks.

Compress Image to Specific Size (KB/MB) — Free Online Tool

Last updated: April 20267 min readImage Tools

You need your image under 100KB for a form upload. Or under 2MB for an email. Or under 200KB for a website. Here is exactly how to hit any target file size — and a free tool that processes everything on your device, no upload required.

Drop your images — compress with quality presets, batch support, before/after comparison.

Open Image Compressor

Target File Sizes — Which Quality Setting to Use

These are typical results for a standard phone photo (4000x3000, 5-8MB original). Actual results vary by image content — photos with lots of detail compress less than simple graphics.

Target Size	Quality Setting	Also Resize To	Typical Use Case
Under 2MB	High (85%)	No resize needed	Email attachments, general sharing
Under 1MB	Medium (65%)	No resize needed	Website images, online forms
Under 500KB	Medium (65%)	2000x1500 or smaller	Blog posts, product listings
Under 200KB	Low (40%) or Medium + resize	1200x900	Web thumbnails, form uploads
Under 100KB	Low (40%) + resize	800x600 or 1000x750	Passport photos, ID uploads, avatars
Under 50KB	Low (40%) + small resize	600x450 or smaller	Tiny thumbnails, profile pictures

Step-by-Step: Compress to a Specific Size

Drop your image into the compressor
Start with Medium quality (65%) — this gives the best balance of size reduction and visual quality
Check the result — the tool shows before/after file size. If it is small enough, download it
Still too large? Two options:
- Drop to Low quality (40%) for more compression
- Resize the dimensions first using the image resizer, then re-compress
Need PNG format? PNG does not compress well with quality sliders. Convert to JPG or WebP for dramatic size reduction. If you must keep PNG, reduce dimensions instead

PNG vs JPG vs WebP — Which Format for Smallest Size?

Format	Compression Type	Best For	Typical Size (1200x900 photo)
JPG at 65%	Lossy	Photos, screenshots	150-300KB
WebP at 65%	Lossy	Web images (25-35% smaller than JPG)	100-200KB
PNG	Lossless	Graphics with transparency	800KB-2MB
PNG (resized)	Lossless + dimension reduction	When PNG format is required	300-600KB

If file size matters more than format, WebP wins. Use the image converter to switch formats, then compress.

Common Scenarios and Exact Workflows

Passport or ID Photo (Under 100KB, specific dimensions)

Crop to the required aspect ratio (e.g., 2x2 inches for US passport)
Resize to the required pixel dimensions (e.g., 600x600)
Compress at Medium quality — at 600x600 dimensions, this easily hits under 100KB

Website Product Images (Under 200KB for fast loading)

Resize to your display size — if your product image container is 800px wide, resize to 800px width
Convert to WebP using the converter for 25-35% smaller files
Compress at Medium quality (65%) — result is typically 80-150KB

Email Attachments (Under 25MB total, preferably small)

Batch compress all photos at once — drop multiple images
Medium quality handles most cases — a 5MB phone photo becomes ~500KB
10 photos at 500KB each = 5MB total, well within the 25MB email limit

Social Media Uploads

Most platforms re-compress your images anyway. But uploading already-compressed images means the platform's re-compression starts from a higher-quality source. Use the social media resizer for exact platform dimensions, then compress at High quality (85%).

When You Actually Need a Dedicated Tool

Browser-based compressors handle 95% of compression tasks. You might need a desktop tool if:

You need exact KB targets with automatic iteration — some desktop tools (like Squoosh CLI) can target a specific byte count and iterate quality until it hits it. Our tool gives you manual control with quality presets instead
You are compressing thousands of images — browser tools handle batches of 50-100 well, but for 1,000+ images, a CLI tool is faster
You need advanced codecs — AVIF, JPEG XL, or other next-gen formats not yet widely supported in browsers

Related Image Tools

Image Compressor — quality presets, batch support, before/after sizes
Image Resizer — change dimensions, maintain aspect ratio
Image Cropper — crop to exact aspect ratios
Image Converter — JPG ↔ PNG ↔ WebP
Social Media Resizer — exact platform dimensions
EXIF Stripper — remove metadata to reduce file size further
PDF Compressor — for document compression

Hit your target file size — compress, resize, convert, all in your browser.