Increase Image Size by the Count, Not by a Mood

Do the division first

Write the long edge you need. A 4×6 at 300 ppi wants 1,800. An 8×10 wants 3,000. A 4K frame is about 3,840. An 8K frame is about 7,680. Divide by the long edge you have. If the ratio is under two, 2× is the whole repair and 4× invents texture you will shrink again. If the ratio is near four, 4× is Pro and two credits. If it is near eight, 8× is Studio and four credits, and it is the jump most likely to invent a surface the camera never recorded.

There is no 3× and no 16K mode. ImgUpscaler.ai has used 16K in a title. We publish 8× and an 8,192 px input cap on Studio, and we do not pretend those are the same claim. A file that is already past 8,192 on the long edge cannot be uploaded to be made larger still. If you already have 8K, you do not have an 8K problem.

DPI and pixels are not the same knob. A 72 ppi tag on a large file is a default, not a small photograph. The print calculator divides pixels by inches or millimetres and tells you the limiting edge. Change the pixel fields to your file. 300 is the hand-held target. 150 can hold a poster from across a room. The tag in the exporter does not add samples.

The free download is its own edge

Guest and Free plan downloads stop at 3,200 px on the long edge even when the preview is larger. That covers a strict 300 ppi 4×6 and 8×10. It does not cover 4K, which is about 3,840, and it does not cover an A4 master at 300 ppi, about 3,508 on the long edge. Pro and Studio keep the full file. The preview is unmarked on every plan, so you can reject the repair before you pay for the size.

Bigjpg’s free tier stops at 3,000 px. Ours stops at 3,200. Neither number is 4K. Their cap is quoted from 26 October 2026. A television that says 4K will scale a honest 1,920 px photograph. Make a true 4K file when a spec, a crop, or a print asks for the count.

Input caps matter as much as output. A guest cannot upload a 3,000 px file. The cap is 2,000. Free plan stops at 2,560. A 2× of a 2,000 px guest upload is 4,000, and the download is trimmed to 3,200. That trim is the product. It is written here so a delivery does not surprise you at the button.

Increase size only after the defect is named

A noisy small file should be denoised before it is enlarged. A soft small file should be unblurred at its own size, then enlarged if the count is still short. A blocked JPEG should be quieted before 2×. Enlarging first prints the defect. The modes are separate so you can see which one moved the pixels. Each has a credit cost. Guests have three credits a day.

Commercial use of the larger file is allowed on every plan when you have the rights to the small one. Making it larger does not create a license you did not have. Free pages show ads. Failures return the credit. Subscriptions cancel anytime and are not refunded. Annual Pro is $120 and annual Studio is $290, which is twelve months for the price of ten.

Download the size you earned the same day. We delete both objects after 24 hours. The API can request the same scales and the same cap applies to a Free plan key. It will not invent a 16K file, and it will not keep one for tomorrow.

A worked frame

You need an A4 page at 300 ppi, about 2480 by 3508, and the photograph is 1600 px on the long edge. The ratio is a little over two. 2× makes 3200, which is short of 3508 on a portrait A4 and inside the free download cap, so you can see the result and still not have the strict A4 master. 4× makes 6400, which clears A4 and costs two Pro credits, and it is justified only if 2× was already honest. If 2× doubled a branch or a window, do not buy the larger error. An 8×10 at 3000 px would have been covered by the free cap and would not need this math. Write the target on paper before you open the tool. There is no 3× to land exactly on 3508. There is no 16K mode if someone asks for a wall graphic by that name. Studio's 8× is the largest scale, and a 1600 px file at 8× is a guess the size of a poster. Prove 2× first. The calculator on the print pages will confirm the ppi after you know which file you are willing to send.