OctosparkOctoSpark
7 free tools

Social media image resizer

Resize an image to the dimensions Instagram, Facebook, LinkedIn, X, TikTok, Pinterest or YouTube expects, entirely in your browser: no upload, no signup.

Which of these resizers do you need

The page you want is decided by where the picture is going, not by what it is a picture of. Each one carries that platform's own published dimensions and exports to them exactly, so choosing the destination is the whole decision.

  • Instagram: everything works back from a single 1080 pixel canvas, and the same photo usually has to be a feed post and a story on the same day.
  • Facebook: the widest spread of surfaces in the family. A feed post, a page header, an event listing and a story are four different shapes, not four sizes of one.
  • LinkedIn: start here for a personal or company banner. They are the two shapes in this family that are strips rather than pictures.
  • X (Twitter): built around what still reads at timeline size, which is a good deal smaller than the picture you are looking at while you post it.
  • TikTok: vertical only. There is no header to fill, and the interface is drawn on top of your frame rather than beside it.
  • Pinterest: the one feed here laid out in columns, so height is the space you are buying and shape decides how much of it you get.
  • YouTube: a thumbnail with the only hard file size ceiling in the family, and a banner most viewers only ever see the middle strip of.

What every platform does to your upload

None of these services keeps the file you send. Each re-encodes it to its own width, its own compression and often its own format, which is why a picture that looked clean on your machine can arrive soft. The only part of that you control is what you hand over.

  • Upload at the width the platform intends to keep. Anything larger is scaled down for you, by a process you cannot see or tune.
  • Compression stacks. A file that has already been through one feed carries artefacts, and the next pass hardens them rather than smoothing them away.
  • The ratio decides the crop, not the pixel count. Two files at the same width and different heights lose completely different parts of the picture.
  • Every avatar in this family is stored square and drawn as a circle, so the corners of what you upload are never seen by anybody.
  • Headers have a safe middle and a disposable outside. What sits near the edges is background that some devices show and others cut.
  • A source smaller than the target cannot be rescued. Scaling up invents pixels, and the platform's own compression pass then finds them.

The mistake that runs through the whole family

Nearly everybody arrives with the same habit: one finished image, reused everywhere, and a shrug at whatever each platform does to it. It is the cheapest thing on this list to fix and the most expensive to leave, because the crop lands on the subject.

  • Reusing a square feed post as a wide link card or a tall story, which hands the choice of which two thirds to discard back to the platform.
  • Resizing a copy pulled back off a feed rather than the original, which is a lossy export of a lossy export.
  • Designing to the edges. Avatars, captions, buttons and reply bars sit on top of your image on most of these platforms, not beside it.
  • Judging the result at full size on a laptop. A feed post, a pin and a thumbnail are all decided at a fraction of the size you made them.
  • Upscaling a small logo to fill a large slot instead of going back for the vector file it came from.

When you do not need a resizer at all

A fair amount of the time the honest answer is to skip this entirely. Every platform here accepts an oversized image and deals with it, and for one quick photo going to one place that is a perfectly sensible trade.

  • A phone photo going straight to a single feed is close enough already. The platform's crop on an ordinary snapshot is rarely what holds the post back.
  • If your source is smaller than the target, resizing makes it worse rather than better. Find a larger file or change the plan.
  • Anything carrying type, a banner, a thumbnail or a pin, is a design job. Build it at final size in a design tool and use a resizer only to check the export.
  • Video is a separate problem. Resizing a cover frame does nothing about black bands in the video playing behind it.
  • One platform, one post, no words on the image: post it and get on with something else.
The rest of the job

You just fixed one post. Now do the month.

The social media image resizer solves one piece of one post. OctoSpark plans, writes and schedules the whole calendar across every network you use, publishes it for you, and reports what actually performed.

  • One calendar for every network
  • Schedule once, publish everywhere
  • Drafts written in your own voice
  • See what actually performed
Open the full sign-up page

No card needed. These tools stay free either way.

Frequently asked questions

How this tool works, what it cannot do, and what happens to what you put into it.

  • What size should a social media image be?

    There is no single answer, which is why this family has a page per platform. Most feed images sit between 1000 and 1600 pixels wide, and it is the shape that differs: a square or 4:5 feed post, a 16:9 or 1.91:1 landscape, a 9:16 full screen story, and headers running from 3:1 to almost 6:1.

  • Can I use the same image on every platform?

    You can, and it will publish. What you give up is the crop decision. A square dropped into a wide slot, or a landscape photo dropped into a vertical feed, is trimmed to fit: the middle survives and everything past the edges of the new frame does not.

  • Do I need an account, and is there a limit on how many images I can resize?

    Neither. The work is done by a canvas in your own browser, so there is no server doing it and nothing to meter or charge for. The files stay on the machine you are sitting at.

  • Why does my image look worse after posting than it did on my computer?

    Because the platform re-encoded it. Every service here recompresses what it receives to its own settings, and the further your upload sits from the size it wanted, the more work that pass has to do. Uploading at the target size leaves it the least to change.

  • Is my data private?

    Yes. This tool does its work in your browser, so whatever you type, paste or upload stays on your device. Nothing is sent to our servers, which is also why it keeps working if you go offline after the page has loaded.

  • Is this really free?

    Yes. Every tool here is free with no account, no credit card and no usage cap. They exist so that the people who need our scheduling product find us, which only works if the tools are genuinely useful on their own.

  • Do I need an account?

    No. Open the page and use it. An account is only for OctoSpark itself, where you plan, schedule and publish a whole calendar rather than fixing one post at a time.

  • Can I use the output commercially?

    Yes. Anything you produce here is yours, including for client and commercial work. We claim no rights over it and we do not watermark it.