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Meet Explayner - turn audio, a talking-head clip, or a simple prompt into a ready-to-post video, right in your browser.

Try Explayner

Upscale Image
Bigger, Honestly

Enlarge photos 2× through 4× using progressive high-quality resampling plus edge sharpening. Classical upscaling, clearly labeled - no AI theater.

2× / 3× / 4×
Sharpening Control
Honest Method
Local Processing
100% Online|No Installation|Private & Secure

Upscaling profile

  • Scale factors2×, 3×, 4×
  • ResamplingProgressive stepped
  • Post-processingOptional sharpening
  • OutputPNG

How to upscale an image

  1. 01Upload your imageSmall photos, old digital images, cropped regions - anything needing size.
  2. 02Choose scale and sharpening2× stays cleanest; higher factors benefit from moderate sharpening.
  3. 03Download the enlarged PNGBigger dimensions with maximally preserved clarity.

Features

Progressive resampling

Stepped 1.4× growth with high-quality filtering beats single-jump scaling noticeably.

Integrated sharpening

Unsharp-mask enhancement counteracts inherent upscaling softness.

Honest positioning

Classical resampling clearly labeled - no pretend AI claims.

Megapixel guardrails

Outputs cap at 40 MP to prevent memory failures.

PNG output

Lossless storage preserves the resampling investment.

Local computation

Enlargement happens on your hardware.

Enlargement needs

Small legacy imagesCropped regionsPrint preparationDisplay scalingIcon enlargement

Honest expectations about upscaling

2× excellence

Doubling with quality resampling looks genuinely good - the sweet spot.

Diminishing returns

3× and 4× grow softer; sharpening helps but physics governs.

Right tool clarity

Better than naive stretching; not magic detail invention.

Use-case fit

Display scaling and modest prints succeed; billboard enlargements need real resolution.

Honest Technology

What upscaling can and cannot do

Upscaling multiplies pixels; it cannot multiply information. A 500×500 image contains exactly the data it contains - enlargement to 2000×2000 interpolates new pixels from neighbors, inventing smoothness rather than detail. Every honest tool works within this constraint; dishonest ones market around it.

Within the constraint, quality varies enormously. Naive stretching assigns each output pixel its nearest source neighbor, producing blockiness. Bilinear interpolation blends immediate neighbors, softening but smoothing. Progressive high-quality resampling with repeated halving-scale mathematics produces the cleanest achievable gradients - the approach used here.

Sharpening then fights the inevitable softness. Unsharp masking exaggerates edges, restoring perceived definition that interpolation diluted. Pushed moderately, it recovers snap; pushed aggressively, it manufactures halos around every boundary. The slider exists because the optimum depends on content and intent.

Notes from people who use this often

“Old listing photos at 640px upscale cleanly to modern minimums - items sell better at proper display size.”

Frank Decker - eBay seller

“Cropped screenshot regions enlarge to slide dimensions without the embarrassment of stretch-blur.”

Irene Castle - Presentation designer

“Small archival photos enlarge enough for exhibit printing - with honest expectations about softness.”

Mohammed Al-Rashid - Museum volunteer

Frequently asked questions

Is this AI upscaling?

No - and that's stated plainly. This uses high-quality classical resampling with sharpening. AI upscalers invent detail; this preserves what exists.

Which scale factor should I choose?

2× produces the cleanest results. Higher factors work but soften progressively - add sharpening to compensate.

Why does the output look soft?

All upscaling softens; interpolation invents no new detail. The sharpening slider counteracts this deliberately.

What's the maximum output size?

40 megapixels - beyond that, browser memory limits risk failures. Very large sources should skip upscaling.

Why PNG output?

Lossless storage preserves the careful resampling; JPEG compression would degrade the enlarged result.

Is processing local?

Yes - enlargement computes entirely on your device.