How much can I compress without losing quality?

JPEG images can typically be compressed to 60–80% of original size with no perceptible quality loss. The tool always targets the highest quality within your limit.

What if it cannot reach my target size?

If the target is below what JPEG alone can achieve, the tool compresses as much as possible. For aggressive reduction, first resize the image to smaller dimensions using the Resize tool.

Does this compress PNG images?

The tool outputs JPEG for smallest file sizes. For PNG size reduction, use Convert Format → WebP, which typically cuts PNG sizes by 30–50%.

How is this different from TinyPNG?

The compression algorithm is similar. The key difference: TinyPNG uploads your image to their servers. myPixelVault runs entirely in your browser with zero upload.

✓ No upload — runs entirely in your browser

Compress Image to Target File Size — Free, No Upload

Set a target in KB or MB — our binary search algorithm automatically finds the highest JPEG quality that fits. No slider guessing. Runs entirely in your browser with zero uploads.

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✓ No file uploads, ever ✓ No account required ✓ 100% free ✓ Works offline

Compress images now

Compress images to exact KB or MB targets — free, no upload

Binary search finds the optimal quality automatically. Processed 100% in your browser.

How image compression works — step by step

Upload your image

Drop your JPEG, PNG or WebP file. The image loads into browser memory — nothing is transmitted.

Set your target size

Enter the maximum file size in KB. Common targets: 200 KB (web), 500 KB (email attachment), 2000 KB (MLS listing). Quick preset buttons apply these instantly.

Binary search runs automatically

The tool runs 14 iterations, each halving or doubling the quality to rapidly converge on the highest quality that produces a file within your target.

Download your compressed image

Click Compress & Download. The result panel shows your original size, compressed size, savings percentage, and JPEG quality level achieved.

File size limits by platform and use case

Platform / use case	Recommended max size	Notes
Gmail attachment	500 KB per image	25 MB total per email
Outlook attachment	500 KB per image	20 MB total limit
WhatsApp image	1 MB	Compressed further on send — start higher quality
Zillow / MLS listing	2 MB per photo	Use 2 MB preset
Amazon product image	2 MB recommended	10 MB technically allowed
Shopify product	1 MB recommended	20 MB limit — small images load faster
WordPress upload	500 KB–1 MB	Default limit often 2 MB; compress before upload
Web page hero image	200 KB	Under 200 KB = fast LCP (Core Web Vitals)
Pinterest pin	500 KB	Smaller files load faster in feed
Instagram post	1 MB	Instagram re-compresses on upload anyway

How binary search compression works

🎯 14-iteration binary search

Instead of one quality setting, the algorithm runs 14 compressions — each halving or doubling the quality based on whether the result is above or below your target. This guarantees the highest possible quality within your limit.

📈 Beats manual sliders

Manual quality sliders (like Photoshop "Save for Web") require trial and error. The algorithm converges automatically — no guessing required.

⚡ Near-instant results

Each iteration runs in the browser using the Canvas API. 14 iterations on a 10 MB image typically completes in under 2 seconds with no network latency.

🔒 Zero server involvement

Tools like TinyPNG, Squoosh (Google), and most cloud compressors upload your image to their servers. myPixelVault compresses entirely in your browser — your image data never leaves your device.

Frequently asked questions

How much can I compress without visible quality loss? ▼

JPEG images can typically be reduced to 60–80% of original size with no perceptible degradation to the human eye. Beyond that, compression artefacts (blocky, blurry areas) become visible. The tool always maximises quality within your target.

What if the tool cannot reach my target size? ▼

If your target is below what JPEG compression can achieve (typically below 15–20% of the original), the tool compresses as aggressively as possible. For extreme size reduction, first use the Resize tool to reduce pixel dimensions, then compress.

Is the output always JPEG? ▼

Yes — JPEG achieves the smallest file sizes for photographic content. For PNG, the best approach is converting to WebP using the Convert Format tool, which typically reduces PNG sizes by 30–50% without quality loss.

How does this compare to Photoshop Save for Web? ▼

Photoshop requires you to manually adjust the quality slider and re-export until you find the right balance. Our binary search finds the optimal quality in 14 iterations automatically — faster and more consistent.

Can I compress multiple images at once? ▼

Batch compression with ZIP download is planned for V2. Join the waitlist on the homepage for early access.