Resize Image to 15 KB
15 KB is a comfortable size for an email-signature logo or a small form photo. This page compresses your image until it fits under 15 KB, without changing its format. Everything runs in your browser — nothing is uploaded. Need different dimensions instead? Resize or convert.
Why compress to 15 KB?
Many sites cap images at 15 KB — typically for signatures, thumbnails and the small photo fields on online application forms. That leaves room for roughly a 300×220 JPG photo.
About 300×220 px fits
At medium quality a detailed JPG photo of roughly 300×220 pixels lands under 15 KB; at high quality about 210×160.
Typical use
15 KB limits are common for signatures, thumbnails and the small photo fields on online application forms.
239× smaller than a phone photo
A 12 MP phone photo is around 3–4 MB, so it must shrink about 239×. The tool lowers quality first and resizes only if needed.
Quality to expect
At 15 KB, quality is basic. Best for small ID photos and signatures.
Scans and documents
A scanned A4 page of about 360×520 pixels usually fits, because text pages compress far better than photos.
Exact limit, checked
15 KB is measured as 15,360 bytes (1 KB = 1,024 bytes), the way most upload forms count it, so the file is never just over.
15 KB at a glance
| Limit in bytes | 15,360 bytes |
|---|---|
| Photo at high quality | about 210×160 px |
| Photo at medium quality | about 300×220 px |
| Photo at low quality | about 410×300 px |
| Scanned A4 document | about 360×520 px |
| Reduction from a 12 MP phone photo | about 239× |
| Output format | JPG (best for photos), WebP or PNG |
| Typical use | Signatures, thumbnails and the small photo fields on online application forms |
Compress an image to 15 KB in 3 steps
- Add your image — JPG, PNG, WebP or a phone photo.
- The target is already set to 15 KB. Leave “Remove EXIF metadata” ticked to save extra bytes.
- Click Compress and download a JPG under 15 KB.
New to image compression? Read the full compression guide.
Light logos for email signatures
Why keep signature images small. An email signature logo is sent with every message. At 15 KB, a hundred emails add 1.5 MB; at 300 KB they add 30 MB — and some mail apps show heavy images as attachments.
Size it for the slot. Signature logos are usually shown at about 150–200 pixels wide. Resize to double that (300–400 px) for sharp retina display, then compress to 15 KB.
Logos: try PNG. A flat-colour logo saved as PNG is often smaller and sharper than a JPG. Photos, on the other hand, stay smaller as JPG.
For forms with a 10–20 KB range, 15 KB lands safely in the middle. Also see 16 KB and JPEG under 15 KB.
Other file-size targets
Nearby limits — each one opens the compressor already set to it:
Compress by format
Guides and presets for each format:
Compress under a file size
Keeps your image’s format — pick the limit you need:
JPEG under a file size
Frequently asked questions
How big should an email signature image be?
Aim for about 300–400 pixels wide and under 15–20 KB. It stays sharp on retina screens and doesn't bloat every email you send.
How many pixels fit in 15 KB?
For a detailed JPG photo, about 300×220 at medium quality or 410×300 at low quality. Simple graphics and scans can be much larger.
What quality will a 15 KB photo have?
Basic. Best for small ID photos and signatures. The tool keeps the dimensions where it can and lowers compression quality first, so faces and text stay readable.
Is 15 KB the same as 15,000 bytes?
Not quite. Most forms count 1 KB as 1,024 bytes, so 15 KB is 15,360 bytes. The tool uses the same count, so a file it marks as under 15 KB is accepted.
Should I use JPG or WebP for 15 KB?
JPG is accepted everywhere and is the safe choice for forms. WebP holds about 30% more detail at the same size, ideal for websites that support it.
Why is my file still over 15 KB?
Very large or detailed images may not reach 15 KB by quality alone. Resize it first (for example to 300 pixels wide) with the resizer, then compress again.
Are my images uploaded anywhere?
No. They are read and compressed by your own browser and never leave your device. You can disconnect from the internet once the page has loaded and it will still work.