Compress Image to 400KB

Reduce any photo to under 400 KB in a few seconds, keeping it sharp. The 400 KB target is already set, so just add your image.

Under 400 KBJPG Runs on your device

Compress to 400KB · Step 1 of 3 · Add your photo

Drop a photo to compress it under 400 KB

or paste with Ctrl+V · JPG PNG WebP HEIC GIF · max 25 MB

Under 400 KB · JPGBatch ready

Processed on this device. Nothing is uploaded.

Example

Before and after

We ran this sample through the compress to 400kb tool above. The numbers under each image are measured from the real files.

Sample input: 5304 x 7952 px · 3.6 MB · JPG — **Before**5304 x 7952 px · 3.6 MB · JPG

Result from this tool: 3448 x 5169 px · 398 KB · JPG — **After**3448 x 5169 px · 398 KB · JPGShown smaller here

How to

How to compress Image to 400KB

1
Add your photo
Choose a photo from your phone or computer. It opens right here.
2
Keep the 400 KB target
The size is already set to 400 KB. Change it only if your form asks for a different limit.
3
Download
Save the result. It is ready to upload straight away.

Why this size

When a 400 KB limit makes sense

400 KB is a comfortable limit for email, marketplaces and websites. Photos keep almost all of their detail while taking a fraction of the original space.

The tool keeps your full resolution whenever it can and only reduces quality as far as it has to.

Upload	Typical limit
Email photo	300-500 KB
Product photo	200-500 KB
Website banner	300-500 KB
Portfolio image	under 1 MB

Use cases

When you need a 400 KB photo

Email attachments

High-quality photos that still fit a strict mailbox limit.

Marketplace listings

Product photos that keep their detail for buyers.

Portfolios

Work samples that look good and upload without errors.

Website hero images

Large banners that stay under your performance budget.

Insurance claims

Clear photos of damage that portals accept the first time.

School projects

Photo-heavy assignments that fit the submission limit.

Tips

Tips that make a difference

Crop first

Cropping to just the face or document removes pixels you do not need, so the quality can stay higher.

Use JPG

JPG gets much smaller than PNG for photos. Use PNG only if the form asks for it.

Check the dimensions too

Some portals also require a size such as 3.5 x 4.5 cm or 200 x 230 px. Set both to avoid a second rejection: resize in cm or in pixels first, then compress.

Plain backgrounds compress better

A plain wall behind you leaves more of the 400 KB for your face.

FAQ

Compress to 400KB: questions

Add your photo above and download the result. The 400 KB target is already set: the tool lowers the JPG quality step by step, and the pixel size only if it must, until the file is just under 400 KB.

Open this page in Chrome or Safari, tap to pick a photo or take a new one, then download. It works on Android and iPhone with nothing to install.

Only if it has to. The tool first lowers the quality at full size, and shrinks the image only when 400 KB is still out of reach.

No. At 400 KB most photos look the same as the original on screen.

The result lands just under the limit, usually within a few percent of 400 KB, so the form never rejects it for being too big.

Add a PNG, HEIC, WebP or JPG photo. The result is always a JPG just under 400 KB, so converting and compressing happen in one step.

Use JPG to PDF under 400 KB: it turns one photo or several pages into one PDF under 400 KB. A PDF upload field rejects a JPG even when the size is right.

No. Compression runs in your browser on your own device. The photo never reaches our servers.

Yes. Drop several photos and each one is compressed to the same target. Download them one by one or together as a ZIP. For a large batch, the bulk image compressor is made for it.

Checked

How we checked this page

Checked by the SizePort team on 3 October 2026.

We test the tool with sample photos before it goes live and check that the sizes on this page match what it produces. Rules and platforms change, so if something here is out of date, tell us and we will correct it.

How the tool works

The compressor first lowers the JPG quality at full resolution, testing several settings until the file is just under the target. Only if quality alone cannot get there does it reduce the width and height, a little at a time. The result is a JPG. Everything happens in your browser; your images are never uploaded.