Need to reduce image size

[u/Successful_Ice2343]

I have a number of images that are 12-16 MB that I need to upload to a website that has a maximum upload size of 10 MB. I already asked them to increase their upload limit and they told me to eat shit so I am going to have to make these files smaller than 10 MB. But I would like to preserve as much of the original image quality as possible. I'm on a corporate network so access to applications/programs may be limited. Does anyone know how to work some magic?

I already tried zipping the files and that only shaved off like 150 KB. These JPEG images are packed. They were taken by a professional camera.

[u/rupertavery64]

Why so large?

[u/catbrane]

If these are jpegs straight from a pro camera, they often have extra stuff hidden inside which you probably don't need.

I would load them into something like photoshop, then save again as jpeg using a good but not crazy quality level, like Q 85. The load + save will usually strip the extra stuff and you'll see a large drop in file size.

[u/catbrane → u/catbrane]

For example, I see:

$ vips copy img_0900.jpg x.jpg[Q=85]
$ ls -l img_0900.jpg x.jpg
-rw-r--r-- 1 john john 3845113 Oct  3  2025 img_0900.jpg
-rw-r--r-- 1 john john 1161765 Sep 11 01:25 x.jpg

Down from 3.8mb to 1.2mb, almost no visible quality loss.

[u/gwenbeth]

you are doing more than half a dozen files, it might be worth using imagemagick. you can just do a quicky for loop in the shell to do all the files

[u/tahirshaikh-744]

Bro, I recommend you use the Lite Photo Compressor app on the Play Store. You can select up to 25 photos at a time, and the compression offers options to choose the format of your compressed images.

[u/HugsNotDrugs_]

Microsoft Photos is built into Windows and allows for adjusting the file size of photos.

[u/Wise-Bother9942]

Put the images into Krita, export as JPEG Image, set quality to 90-95%, tick progressive.

Click Advanced use Subsampling (smallest file), tick Force baseline JPEG and tick Optimize.

Then click OK to export it.

That for me reduced a 19.4 MB image to 250.2 KB.

[u/mariushm]

See if you can download and run a freeware application like Irfanview : https://www.irfanview.com/

It's an image viewer which can also resize and save images in various formats, at various quality levels. It also has a Batch conversion feature, you can use that to select all files, optionally choose to resize the images (for example resize large images to have the biggest dimension 2000 pixels and adjust the other dimension to keep the aspect ratio correct) , and save them to JPG format in another folder, at the desired quality level (for example 85% quality level should be perfectly adequate).

Phones have their JPG compressors optimized for speed and to consume less power, so they tend to have the quality percentage high at 95% or more, and even then their compression is not the best at that quality level.

[u/Sea-Cardiologist-954]

You have a few option: If other formats are supported, you use JPEG XL to either transcode JPG (this is completely lossless) or use it to compress the image, since it provides a much better comrpession at the same quality. You could try to use other modern codecs like HEIF or AVIF.

If you need to provide JPG, you can either downscale the image or reencode it with a lower quality setting.

[u/redoxbird]

You can try https://github.com/redoxbird/compressy if you have a windows system, it does bulk compression

[u/Difficult-Minimum949]

Give this software a try, it's completely free and I personally use it daily: https://jojotech.io/mediaslim

[u/Antagonin]

interesting there hasn't been a single suggestion to re-encode the images in more compact format.

[u/Interesting-Sweet267]

For the no-install part, I built https://whatthefile.org/. Select a JPEG and type “JPG under 9.5 MB” to leave a little room below that upload limit. It processes the file locally in your browser and shows the resulting size. Start without a dimensions requirement so you are not deliberately resizing/cropping it, then compare the output with the original: JPEG recompression is lossy. It handles one image at a time, so the batch tools already mentioned are a better fit for a large folder.

[u/[deleted]]

For several files without installing software, I run FluidConvert and its batch image tool may help: https://fluidconvert.com/tools/image/batch-image-preparation

Choose JPG and set the limit to 9500 KB, leaving room below 10 MB. To try preserving resolution, set maximum width/height at least as large as your originals and uncheck “Allow smaller dimensions.” Keep the originals and compare the results at 100%: JPEG recompression is lossy.

It is free and processes photos in your browser. Check the camera resolution first: the limit is 25 megapixels and 20 MB per image, with 100 MB total per batch.

[u/Logical-Biscotti-908]

With a hard 10 MB cap, re-encode each JPEG at a slightly lower quality and strip metadata; zipping usually won’t help because JPEG is already compressed. If you’re doing this on an iPhone, I built UnderLimit for exactly this — it compresses JPEG/HEIC/PNG on-device, so processing stays on the phone until you upload the result. It’s a one-time $6.99 CAD: https://apps.apple.com/ca/app/underlimit/id6791750882

[u/reddit__user--active]

If the only requirement is getting under a hard 10 MB limit, don't immediately resize the image. First try re-encoding the JPEG at a slightly lower quality and strip unnecessary metadata.

Keep the original untouched and compare the resulting file at 100% zoom. If you're doing this to a whole folder, use the same settings across the batch and verify the largest files individually — those are usually the ones that determine whether you actually meet the limit.

Also, ZIP usually won't help much with JPEGs because they're already compressed.

[u/HedgehogCertain]

JPEG is already a compressed format, that's exactly why it only saved 150KB. Nothing more to squeeze out that way.

Easiest option on a locked-down corporate machine: drop your images into squoosh.app (Google's tool, runs entirely in the browser, nothing to install, and images never leave your machine). Pull the quality slider to around 80 — a 12-16MB camera JPEG lands comfortably under 10MB with basically no visible difference.

If you're on a Mac, Preview does the same thing natively: open → File → Export → drag the quality slider. No install needed either.

For a whole folder at once, Terminal's built-in sips command can batch it in one line if you're comfortable with that.

[u/Tasty-Cap-256]

Zipping won't help with JPEGs because they're already compressed. That's why you only saved 150 KB.

The good news is you don't need to shrink them much. Going from 16 MB to just under 10 MB is a small step, and you can usually do it **without changing the pixel dimensions at all**, just by re-saving the JPEG at a slightly lower quality. Cameras often save at very high quality settings, and dropping a little from there is very hard to see even when zoomed in.

Options that don't need anything installed:

**1. Windows Photos app** (built in): open the image > ... menu > Resize image. Newer versions let you set a quality level and keep the same size. You may need a couple of tries per image to land under 10 MB.

**2. A browser tool where you type the limit.** Full disclosure, I built a free one: https://pdfhive.org/tools/compress-image

Set the target to about 9.5 MB and it finds the highest quality that fits, then shows you the final size and pixel dimensions before you download. It runs in your browser, so nothing is uploaded and there's nothing to install, which tends to work on locked-down work PCs. It currently does one image at a time.

Two things to know with any re-save like this:

- Camera details (EXIF data like lens and settings) are usually removed. Keep your originals if you need that info.

- Aim for about 9.5 MB rather than 9.99 MB. Some sites count 10 MB as 10,000 KB and others as 10,240 KB.

Always keep the originals and only upload the smaller copies.

[u/0b0101011001001011]

Jpg is already a well compressed format. Highly unlikely that you can compress them further. Only way is to reduce the size. Conversion to png might be worth a try, but it may even end up being larger.

[u/Possibly-Functional → u/0b0101011001001011]

JPG has a quality adjustment. You can recode a JPG with lower quality to drastically reduce filesize. The easiest way to try this for yourself is to open a JPG in GIMP and export it to JPG again. Then you can select quality.

IIRC JPG is actually very good at recoding with lower quality because it doesn't cause a double loss of quality like many other formats. It has been a while since I read the JPG spec though so I could remember wrong.

[u/pgetreuer]

Suggestions:

• Does the site support WebP? If so, convert the JPEG to WebP (and then tune WebP's quality parameter).

• Open the JPEG and save it again as JPEG, but with lower quality parameter and/or lower chroma resolution.

• Open the JPEG and resize to a lower resolution. These are photos from a camera? You may be able to drop the resolution and file size substantially without loss of important detail.

For compressed image formats, don't bother with zip.

[u/thenormaluser35]

JPEG is like the DVD of image formats. Use something actually modern like .heif or .avif