You have a folder full of images and a platform that gives you three unhelpful choices: a website asking for WebP, a logo that must sit on a transparent background, and an email form that rejects anything but JPG. Each format exists for a reason, and picking the wrong one shows up immediately — either as a 15 MB web page, a white box around your logo, or an attachment that won't open on your client's phone.
This guide cuts through it. No history lesson, no vendor hype — just a decision table, the honest limits of each format, and a click-path to convert whatever you have into the format the job actually needs. Every converter linked below runs in your browser, so your files are never uploaded.
The one-line answer
Photos on the web → WebP, with a JPG fallback. Logos, icons and screenshots with transparency or sharp text → PNG (or WebP if it stays on the web). Email attachments, government forms and print orders → JPG.
The rest of this page explains why, so when a platform gives you a confusing instruction ("convert to WebP", "PNG required", "JPG only") you know exactly which side of the rule you are on.
At-a-glance comparison table
The numbers below describe typical, real-world behavior. Exact kilobyte savings vary wildly from image to image — a detailed landscape compresses very differently from a flat headshot — so treat them as planning estimates rather than promises. Verified against Google's WebP documentation and MDN's format guide on 2026-10-06.
| Format | Compression | Transparency | Animation | Best for | Typical size vs. JPG | Support |
|---|---|---|---|---|---|---|
| JPG (JPEG) | Lossy only | No | No | Photographs, print, email, universal forms | Baseline (1×) | Universal, everywhere since the 1990s |
| PNG | Lossless | Yes (8-bit alpha) | No (APNG exists, rarely used) | Logos, icons, screenshots, flat graphics, transparent layers | 2–3× larger for photos | Universal |
| WebP | Lossy and lossless | Yes (8-bit alpha) | Yes (animated WebP) | Web photos, transparent web graphics, animation | ~25–35% smaller than JPG; ~26% smaller than PNG | All modern browsers (Chrome, Edge, Firefox, Safari 14+); not reliable in email |
A note on AVIF: AVIF compresses slightly smaller, but support is still uneven. PixlReady exports JPG, PNG and WebP — the three formats that cover nearly every real task — and this guide sticks to those.
JPG / JPEG — what it's good and bad at
JPEG turned 30+ years old and is still the default because it does one thing extremely well: it compresses photographs. Its lossy algorithm exploits the fact that the eye barely notices fine color detail in busy areas, so a 12-megapixel outdoor shot drops from 30 MB to 3–5 MB with almost no visible loss.
Good at
Photographs with continuous tones — faces, landscapes, products. It is the only format every email client, form, photo lab and old device will open, and the safest choice when a platform recompresses your image anyway (social networks crunch whatever you upload).
Bad at
Three things, always: transparency (it has none — see through areas flatten to white), sharp flat edges (text, logos, icons come out fuzzy with ringing halos), and repeated editing (every re-save throws away more data). If your image has a checkerboard background or crisp lettering, JPG is the wrong tool.
PNG — what it's good and bad at
PNG is lossless: what you put in is exactly what comes out, pixel for pixel. It also carries a full 8-bit alpha channel, meaning every pixel can be partially transparent — not just on/off. That combination makes it the world default for graphics.
Good at
Logos, icons, screenshots and anything with text or hard edges. The lossless encoding keeps lettering crisp, and the alpha channel lets a logo float over any background — the same family you want for a transparent signature on a PDF.
Bad at
Photographs. Because it stores everything losslessly, a photo saved as PNG typically runs 2–3× larger than the same photo as JPG. A full-res PNG hero image can weigh 8–15 MB — enough to wreck a page's loading speed all by itself. Never use PNG as a photo format on a website.
WebP — what it's good and bad at
WebP, developed by Google, is designed to do JPG's job and PNG's job in one format. It supports lossy compression and lossless compression and full alpha transparency and animation — all in a file smaller than whichever classic format you are replacing.
Google's own WebP FAQ states that, at equal visual quality, lossy WebP is about 25–34% smaller than JPEG, and lossless WebP is about 26% smaller than PNG. On a blog or product page with ten images, that is the difference between a 3 MB page and a 2 MB page.
Good at
Anything delivered through a modern website: photographs, transparent logos on the web, even short looping clips (animated WebP replaces GIF at a fraction of the size). Every browser released since around 2020 — Chrome, Edge, Firefox, and Safari from version 14 onward — renders it natively.
Bad at
Anything where you do not control the renderer. WebP does not display reliably in Outlook or Gmail, some legacy uploaders reject the extension, and old publishing software cannot open it. Whenever the recipient's software is a question mark, ship JPG or PNG. The safe web pattern is WebP for the page with a JPG fallback.
Which format for which job
If you only remember one table, remember this one. Match your task to the row, then convert the source file with the linked tool.
| Your task | Use this format | Why |
|---|---|---|
| Website photos, blog images, product shots | WebP (keep a JPG fallback) | Smallest lossy file; pages load faster; all modern browsers support it |
| Logo, icon, or anything meant to float on a see-through background | PNG (or WebP if it is web-only) | Only PNG and WebP hold true transparency; JPG flattens to white |
| Screenshot, UI mockup, image with text | PNG or WebP (lossless) | Keeps edges and lettering sharp without ringing |
| Email attachment, government form, visa portal, print order | JPG (or PNG if transparency is required) | The only format every legacy renderer accepts |
| Short looping animation | Animated WebP (or MP4 for video) | Dramatically smaller than a GIF; still avoid it in email |
| Photo you must re-edit later | Keep a master (PNG/TIFF), export JPG/WebP for delivery | Every JPG/WebP lossy re-save degrades the image one more notch |
How to convert between them
Converting is where this guide pays off: once you know the target format, one click does the rest. All of these run locally in your browser — nothing is uploaded.
- JPG → WebP to slim a photo-heavy web page: open the JPG to WebP converter, drop in your photos, download. Expect roughly a quarter of the file weight to disappear.
- PNG → WebP for a transparent logo on the web: use the PNG to WebP converter. Transparency is preserved, and the file shrinks further. Keep a PNG copy for anything that drops into PDFs or desktop apps.
- WebP → JPG when a portal, form or email rejects WebP: the WebP to JPG converter flattens and re-encodes to the universal format. Heads-up: any transparency is lost and rendered on white, so only do this for photos.
- Flatten a transparent PNG to JPG for a JPG-only form: use PNG to JPG. The reverse — adding transparency to a photo — needs the background remover, not a converter.
- Need to convert a whole batch, or pick the format in one interface? The master format converter handles JPG, PNG and WebP both directions.
One more situation: iPhone photos arrive as HEIC files nobody can open — see our guide on converting HEIC to JPG. The end format is usually JPG or WebP, exactly the decision table above.
Common mistakes
- Saving a logo as JPG. The dead giveaway is a white box where the transparency should be. JPG simply cannot store alpha — re-export as PNG or WebP.
- Using PNG for hero photos. A 12 MB PNG on your homepage slows every visitor. Resave it as WebP (or JPG as a fallback) and watch the page weight drop by three-quarters.
- Assuming WebP renders in email. It usually does not. Campaigns and invoices go out as JPG; the WebP lives only on your website.
- Re-saving JPEGs over and over. Each export at quality 70 throws away another slice of detail. Keep one lossless master and always re-export from it.
- Ignoring the file weight. Even the right format can be too heavy for a form. If a portal rejects your export, trim it with a browser compressor (see our no-upload compressor guide).
Common questions
Is WebP actually better than JPG?
Yes, for photographs on the web. At equivalent visual quality, lossy WebP files are roughly 25 to 34 percent smaller than JPEG, and lossless WebP is about 26 percent smaller than PNG, according to Google's own WebP measurements. The catch is compatibility: WebP is safe in every modern browser, but it does not render reliably in email clients or in some old software, so you keep a JPG fallback ready.
Why shouldn't I just use PNG for everything?
Because photographic PNG files are typically two to three times larger than the same photo saved as JPG. PNG is lossless, which is wonderful for logos, icons and screenshots with sharp edges, but a lossless 12-megapixel photo can easily weigh 8 to 15 MB. On a web page that extra weight costs loading speed, which is why photographers and developers use JPG or WebP for photos and reserve PNG for graphics that need transparency or crisp text.
Does WebP support transparency?
Yes. WebP supports a full 8-bit alpha channel in both its lossy and lossless modes, the same way PNG does, and the transparent file is usually smaller. JPG, by contrast, has no transparency support at all — a transparent area exported as JPG is flattened onto white. If you need a see-through background, choose PNG or WebP, never JPG.
Will WebP images break on old browsers or in email?
On the web, no: WebP has been supported by Chrome, Edge, Firefox and Safari since Safari 14 (2020), so every current browser renders it. In email and in legacy desktop apps, yes, it can break. Email clients such as Outlook often ignore WebP entirely, and some older CMS uploaders reject the extension. When you cannot control the renderer — an email attachment, a government form, a print shop — send JPG or PNG.
Which format is best for logos and icons?
Use PNG for a logo or icon that must keep a transparent background and be dropped into arbitrary apps, PDFs and documents. Use WebP only when the graphic lives purely on a modern website and you want the smaller file. Never save a logo as JPG: its lossy compression smudges flat edges, and any transparency collapses into a visible white box.
Should photos for print be saved as WebP?
No. Print shops and photo labs expect TIFF or a high-quality JPG, and very few prepress tools can open WebP. Send JPG (or TIFF) for print. WebP is a screen delivery format, designed to make web pages load faster, not to be passed into a print pipeline.
How much smaller is WebP than JPG, really?
Google's published measurements put lossy WebP at about 25 to 34 percent smaller than JPEG at equal visual quality, and the common practical phrasing is 25 to 35 percent. In practice the saving depends on the image: a detailed landscape benefits more than a flat headshot. Exact kilobytes vary wildly by content, so treat the percentage as a planning estimate, not a guarantee for any one file.