FileLarkThe exact size YouTube wants — in one click
YouTube thumbnails must be 1280×720 pixels (16:9), under 2 MB, ideally JPG. Miss any of those and YouTube Studio rejects the upload or your image arrives cropped in ways you didn't choose. This tool takes any image — a photo, a screenshot, a design export, even an iPhone HEIC — and produces a thumbnail that passes every requirement, instantly.
If your image isn't already 16:9, you choose what happens: crop-to-fill keeps the frame full (best for photos), or fit-with-bars preserves the whole image letterboxed on black (best for artwork you can't crop).
Why 2 MB trips people up
Design tools love exporting thumbnails as PNG, and a detailed 1280×720 PNG regularly lands over the 2 MB cap. This tool always outputs an optimized JPG — visually identical at thumbnail sizes and reliably a fraction of the limit — and automatically steps the quality down in the rare case a JPG would still be too large.
Unlike most online converters, FileLark never uploads your files to a server. The conversion runs entirely inside your browser using modern web technology, which means it works offline once the page has loaded, there are no file size queues or daily upload limits, and your images can never be stored, scanned, or leaked — they simply never leave your device.
More thumbnail workflows
Need a competitor's thumbnail for reference or your own back from an old video? The YouTube thumbnail downloader grabs any video's thumbnail in every quality. Designing from a photo? Remove the background first for that clean cut-out-subject look every big channel uses, then resize the finished design here. And our thumbnail size guide on the blog covers dimensions, safe areas and design tips in depth.