Reduce Image Dimensions
Quarter, Half, Three-Quarters
The fastest way to shrink photos: scale by percentage. Drop to 50% and file sizes typically fall 60-75% with no visible difference at viewing size.
Reduction cheat sheet
- 50% scale~75% fewer bytes
- 75% scale~45% fewer bytes
- 25% scale~94% fewer bytes
- QualityResampling-preserved
Explore related tools
Different jobs, same file here's what people use alongside this tool.
How to reduce image dimensions
- 01Drop in your photosOne image or an entire folder's worth.
- 02Drag the scale sliderWatch the computed output dimensions update live.
- 03Download the smaller setProportionally scaled copies, original files untouched.
Features
Slider simplicity
No numeric entry - find the right scale visually.
Proportional guarantee
Both axes scale together; distortion is impossible.
Stepped resampling
Deep reductions use progressive halving for clean results.
Format retention
Stay in your format or switch output while you're here.
Batch-native
Entire shoots reduce in one pass.
Instant iteration
Adjust the slider and rerun without re-uploading.
When percentage reduction fits
Small math, big consequences
Pixels square, bytes follow
Linear scale reduction compounds quadratically in file size - 50% linear means 25% the pixels.
Screen reality
Most displays show images far below camera resolution; excess pixels are invisible weight.
Speed of habit
A five-second reduction pass before sharing beats post-hoc cleanup every time.
Reversible decisions
Originals persist; reduction creates copies, never destroys.
Why 50% is the magic number
Scaling to exactly half has a pleasant property: every output pixel corresponds to a neat 2×2 block of source pixels, which resamplers average cleanly. Odd factors like 37% force messier sampling patterns that can subtly roughen fine detail. When in doubt, halve.
The byte mathematics are steeper still. Halving linear dimensions quarters the pixel count, and since encoded size tracks pixel count closely, files shrink roughly four-fold. A 6 MB phone photo becomes 1.5 MB; run it again and you're at 400 KB - often without visible change at social-media display sizes.
Percentage thinking also survives contact with unknown requirements. Told an image is 'too big' but given no spec? Halving is the correct first move, with another halving held in reserve. It's the dimensional equivalent of turning it off and on again.
“Scan day used to produce 40 MB PDFs of images. Halving everything first changed that permanently.”
Ruth Adeyemi - Office manager
“My shared albums finally load on my parents' connection after a blanket 50% pass.”
Paulo Oliveira - Hobby photographer
“Newsletter photos at 50% look identical in print layout and attach ten at a time now.”
Sandra Kim - PTA volunteer
Frequently asked questions
How much smaller will my file be at 50%?
Typically 60-75% smaller, since halving dimensions quarters the pixel count and encoding follows.
Will 50% reduction look worse?
At normal viewing sizes, essentially never. The detail removed was beyond what screens display anyway.
Can I go below 25%?
The slider reaches 5% for thumbnail territory, though extreme reductions belong in dedicated thumbnail workflows.
Does percentage mode keep aspect ratio?
Always - both dimensions scale by the same factor, making distortion mathematically impossible.
Can I enlarge instead?
Yes, up to 200%, though enlargement softens detail regardless of tool quality.
Is batch reduction slower?
Each file processes independently; total time scales linearly with count.