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Image converter: WebP, PNG and JPG, in your browser

Save a WebP or a PNG as a JPG, or a JPG as a PNG, up to twenty pictures at once. Free, in your browser; nothing is uploaded.

By Mellow · Updated October 12, 2026

Save a picture as another type

Choose picturesUp to 20 at a time. They stay in this page: nothing is uploaded.

Opens everywhere, and the smallest file for a photograph. No transparency. This browser cannot write WebP, so it is not offered here.

Quality: 90

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Which image file type should I use for social media?

A JPG is the safe one. Instagram, through its API names JPEG and nothing else, and each of the 6 places in the table below takes it. A WebP, which is what a picture saved from a website often is, is named by 1 of the 6. So a WebP or a PNG that will not upload is usually fixed by saving it as a JPG, which is what this converter does.

The file types each network names

Where	File types its page names	Source
Instagram, through its API	JPEG	Instagram Graph API, IG User media (image specifications)
Threads, through its API	JPEG, PNG	Threads API overview, media specifications
TikTok photo posts, through its API	JPEG, WebP	Content Posting API, media transfer guide
YouTube thumbnail	JPG, PNG	Add custom thumbnails on YouTube
X profile and header photos	JPG, GIF, PNG	How to customize your profile
LinkedIn Page images	PNG, JPEG	Image specifications for your LinkedIn Pages and Career Pages

Every row is from the network’s own page, read on 12 October 2026. JPEG and JPG are the same type. Several rows are about posts made through a network’s API, which is what scheduling tools use; what a network’s own app accepts from your phone is often wider and is not published. A place that names no file type is not in the table.

JPG, PNG or WebP?

JPG for photographs: a small file that opens everywhere. No transparency.
PNG for screenshots, drawings and anything transparent: every pixel exactly, in a larger file.
WebP for a website: smaller than a JPG at the same quality, but named by few networks.

Questions

How do I convert a WebP to a JPG?

Choose the picture, leave JPG chosen and save. The converter opens the WebP in your browser and saves it again as a JPG at its own size. Up to twenty pictures can be done at once; several come as a ZIP, or go straight to Photos on a phone.

Which file types do the networks take?

Instagram, through its API: JPEG; Threads, through its API: JPEG, PNG; TikTok photo posts, through its API: JPEG, WebP; YouTube thumbnail: JPG, PNG; X profile and header photos: JPG, GIF, PNG; LinkedIn Page images: PNG, JPEG. Each is from the network’s own page, read on 12 October 2026, and listed in the table on this page.

What happens to transparency?

A PNG and a WebP keep it. A JPG cannot: where the picture is transparent you choose white or black to stand behind it.

Does converting change the size or the quality?

The pixels stay the same, unless the picture is over 16 megapixels, which is made that size first. A PNG is saved exactly; a JPG or a WebP is saved at the quality you set, 90 to start with.

Why is there no WebP choice in my browser?

Some browsers, Safari among them, cannot write a WebP from a page: asked for one, they hand back a PNG. The converter checks, and offers WebP only where the file really is one.

Are my pictures uploaded?

No. The pictures stay in this page and are converted in your browser; the files are made on your own device.

The right file type; now post it everywhere at once

Mellow Hub takes one post to the networks you connect, now or at a time you choose, and checks each network’s rules before anything is sent. Is the file too heavy rather than the wrong type? The image compressor brings it under a network’s limit.

Post to Instagram and TikTok at once

Every social media image size, with sources

This tool is free and needs no account. Mellow Hub publishes your first 3 posts free, with no card; after that it is paid, with a 7-day free trial. It publishes only what you, or an assistant you have authorised, send or schedule.

Choosing a scheduler? Mellow Hub next to Buffer, Metricool and Postiz, from each one’s own pricing page, including where another is cheaper.

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