HEIC → JPEG · never over your limit
Compress HEIC to your size limit.
Type the size the form asks for — 100, 50, 200 KB — and get a photo at or under it. Nothing is uploaded.
- Never over your limit
- No upload
- Free, no signup
Quick answer
What does HEIC To Size do?
HEIC To Size turns one HEIC or HEIF photo into a JPEG or PNG that is at or under the size you choose. Everything happens in this browser; the photo is never uploaded.
| You bring | One HEIC / HEIF photo |
|---|---|
| You get | JPEG or PNG |
| Size limit | 5–5000 KB; the result is always at or under it |
| Where it runs | In this browser; the photo is not uploaded |
To fit a smaller limit, JPEG quality is lowered, but never below a set floor; if the file is still too big, the photo is reduced in pixel dimensions. PNG uses lossless encoding, so it fits by reducing pixel dimensions only. No tool can make a file much smaller without changing the picture or its dimensions.
How HEIC To Size hits your limit
Most image compressors give you a quality slider and leave you to guess. Upload forms do not care about quality. They care about file size. HEIC To Size starts from the size limit and works backwards, in four steps that all run inside your browser tab:
- Open the photo. The tool brings its own HEIC reader (written in Rust, running as WebAssembly), so it works even in browsers that cannot show HEIC photos themselves. The photo's colour profile (often Display P3 on iPhones) is read and kept.
- Find the best quality that fits. The tool tries JPEG quality settings between 100 and a floor of 55 and keeps the highest one whose file is at or under your limit.
- Make it smaller only if it has to. If even quality 55 at full size is too big, the picture is made smaller in pixels (Lanczos3 filter) and the search repeats, until the file fits. This is why very small limits give you a smaller picture rather than a blurry, blocky full-size one.
- Hand you the file. The result is shown next to the original with its exact size, dimensions and quality, and you download it straight from the page. Nothing is uploaded, stored or logged.
PNG works differently because PNG never loses quality (it is lossless) and has no quality setting: the tool makes the picture smaller in pixels until the file fits, then grows it back in small steps from the original to use as much of your limit as possible. For photos, JPEG almost always keeps more detail at the same file size; choose PNG only when a form requires it.
Measured results, not estimates
These rows come from running the same code this site uses on fixed test photos from the project repository (Apple Silicon Mac, 2026-09-24). The same photo always gives the same file size, dimensions and quality, so anyone can reproduce them from the open-source code.
| Photo | Original | Limit | Result | Dimensions | JPEG quality |
|---|---|---|---|---|---|
| iPhone photo A | 1,334,866 B · 3024×4032 | 50KB | 50,560 B | 596×795 | 56 |
| iPhone photo A | 1,334,866 B · 3024×4032 | 100KB | 101,650 B | 850×1133 | 60 |
| iPhone photo A | 1,334,866 B · 3024×4032 | 200KB | 203,649 B | 1240×1653 | 61 |
| iPhone photo B | 570,547 B · 3024×4032 | 100KB | 102,154 B | 1290×1720 | 63 |
| iPhone photo B | 570,547 B · 3024×4032 | 200KB | 203,545 B | 1824×2432 | 62 |
Two things are worth noticing. Quality stays around 55–63 at every limit, because the floor stops it from collapsing. And doubling the limit from 100KB to 200KB roughly doubles the pixel count of photo B at nearly the same quality — so if a form allows 200KB, use all of it. The full table, including a non-iPhone camera photo, is on Reduce HEIC file size.
Which size should you type?
Always type the exact maximum the form states, not a round number below it: a bigger limit means more pixels and more detail. Go one or two KB under if the form's own counter seems to round up. Limits you are likely to meet:
| 20–30KB | Very tight caps on older exam and recruitment portals, small signature or thumbnail fields. | 20KB guide30KB guide |
|---|---|---|
| 50KB | Strict application forms and avatar uploads that need a recognisable face, not a detailed photo. | 50KB guide |
| 100KB | The most common ceiling on government, school and job-application forms. | 100KB guide |
| 200KB | Visa and document-scan uploads that allow a more detailed image. | 200KB guide |
| 500KB | Email attachments, marketplace listings and support tickets where the limit is loose but the original is still too big. | 500KB guide |
If you only need a JPEG or PNG and have no size limit, use HEIC to JPEG or HEIC to PNG instead: converting keeps the full resolution (JPEG at quality 95, PNG with no quality loss) rather than aiming for a size.
What happens to your photo
The tool itself is downloaded once (as a WebAssembly file) and runs on your own device. Your photo is opened in the page, made smaller and offered back as a download; it is never sent to a server, and it is gone when you close or refresh the tab. This matters for the kind of images people usually shrink for forms — passports, ID cards, certificates and faces. You can verify it yourself: open your browser's developer tools, switch to the Network tab and compress a photo; you will see that nothing carrying the image is sent. The details, including what the page itself does measure, are in the privacy policy.
Questions people ask
Why does a website reject my iPhone photo?
Since iOS 11, iPhones save photos as HEIC by default. Many upload forms only accept JPEG or PNG, and most also cap the file size. A typical iPhone photo is 1–5 MB, so it fails both checks at once. This tool fixes both in one step: it converts to JPEG (or PNG) and brings the file under the limit you type.
Why is my result a little smaller than the target, not exactly equal?
Your number is a ceiling, not a goal. The tool keeps the best JPEG quality that still fits, and one step better would go over. Ending a few hundred bytes under your limit is normal; ending over it never happens.
Why did the resolution go down?
Below JPEG quality 55 photos start to look blocky, so the tool never goes lower. If the full-size photo still does not fit at quality 55, it makes the picture smaller in pixels (with a Lanczos filter, which keeps edges clean) until it does. For small limits like 50KB, a smaller picture at decent quality looks better than a full-size one at very low quality.
Does 1KB mean 1,000 or 1,024 bytes here?
The tool uses 1KB = 1,024 bytes, which is how Windows and most upload forms count. A 100KB limit means the file is at most 102,400 bytes. If a form counts 1KB as 1,000 bytes, type a slightly smaller number, for example 97 instead of 100.
Is my location or camera information kept?
No. The result is a brand-new file, so the hidden details in the original (EXIF: camera model, date and any GPS location) are not copied. The colour profile is kept so colours do not shift.
Can I use it offline or on a phone?
It works in current Chrome, Edge, Firefox and Safari on desktop and mobile. Once the page has fully loaded it no longer needs the internet, because nothing is sent to a server.
HEIC To Size is an independent, open-source project. About the project and how it is tested.