How to use GIFsize

Drop in a video or GIF, pick the size limit of where it’s going, and make it. That’s all.

The basics

1. Add a file — Drop an MP4, WebM or MOV video, or a GIF, onto the converter. Nothing is uploaded; it’s processed only in this browser.
2. Set a target size — Turn on “Fit to a target size” and drag to the limit of where you’re posting (1–50MB, or type any number), and the width and frame rate are chosen for you.
   • Sharper: keeps the picture as large as possible and lowers the frame rate first. Best when text or product detail matters.
   • Smoother: keeps the motion (frame rate) and shrinks the size first. Best when movement matters.
3. Fine-tune (optional) — Range, speed, reverse/ping-pong, crop, rounded corners and text. The estimated size updates with every change.
4. Make GIF → Save — If the result goes over your target, it’s automatically re-made one step smaller.

How is the size estimated?

When you open a file, the whole clip is scanned once at low resolution and the real conversion is simulated from start to finish. A few scenes are then compressed at full size to scale the result up. A 10% safety margin is added, so the real file usually comes out a little smaller than the estimate.

While “Detailed analysis” is shown under the estimate, the number is provisional. It becomes more accurate once the analysis finishes.

Tips for smaller GIFs

• Keep it short — Size grows almost in proportion to the number of frames. Keeping only the motion you want to show helps the most.
• Speed it up — At 2× the same action takes half the frames. Great for product demos.
• Crop — Cutting away unneeded background reduces the pixel count and the size with it.
• 10–15 fps — Most product GIFs look natural at around 12 fps.
• Keep the moving area small — The steadier the background, the more “Skip unchanged pixels” saves. A video shot on a tripod helps.
• Ping-pong with care — It roughly doubles the frames, and so the size.

FAQ

Is my video really not uploaded?

Correct. Reading the video, extracting frames, compressing to GIF and saving all happen inside the browser you’re using. There is no upload feature at all — once the page is open, conversion even works offline.

Why is my GIF bigger than the original MP4?

GIF is a format from 1987 and compresses far less efficiently than modern video codecs like H.264, so a GIF several times larger than the MP4 is normal. Choose a target size and GIFsize will shrink the dimensions and frame rate to fit.

My video won’t open (AVI, some MOV files…)

Only formats your browser can play are supported. MP4 (H.264) and WebM almost always work; AVI or MOV with unusual codecs may not. Re-save it as MP4 with a tool such as VidCut first.

Does it work on phones?

Yes, but phones have less memory, so long videos or large sizes may be slow or fail. Short ranges at 480px or less are recommended.

Transparent rounded corners look jagged

GIF pixels are either fully transparent or fully opaque — there’s no partial transparency for smooth edges. Choose the background color of the page where you’ll post the GIF (usually white) and the corners will look smooth.

How do I use fonts installed on my PC?

In Chrome or Edge on desktop, the “My PC fonts” button lists your installed fonts (it asks for permission once). In other browsers, load a TTF, OTF or WOFF file with “Font file”. Font files aren’t uploaded either.

Is there a watermark? Can I use the result commercially?

No watermark is added. The GIF is yours to use as long as you have the rights to the original video.

The estimate and the real size differ

Estimates lean toward the safe side, but some videos still differ. After one conversion, estimates for that file are corrected using the real result. With a target size selected, a result that goes over is re-made automatically.