Everything a YouTube creator needs to know about titles, descriptions, tags, and thumbnails — plus the free tools to check each one.
A YouTube video succeeds or fails based on a handful of metadata decisions made before a single view happens: the title, the thumbnail, the first line of the description, and the tags attached behind the scenes. None of these are complicated on their own, but each has specific technical limits that are easy to get wrong without realizing it — a title that reads fine in the editor but gets truncated in search, a thumbnail that's the wrong resolution, a tag list that silently drops entries past the character limit.
This guide walks through what each piece of metadata actually does, the limits that govern it, and the free tools on this site that check each one before you publish.
YouTube allows up to 100 characters in a title, but search results and suggested-video placements typically show only 60 to 70 characters before truncating with an ellipsis — and mobile screens often show even less. The practical rule: put the part of the title that actually explains the video within the first 60 characters, and treat anything past that as a bonus some viewers will see and others won't.
Check any draft title against this cutoff with the YouTube Title Checker, which shows a live search-result preview as you type.
A YouTube description can run up to 5,000 characters, but only around the first 150 show before a viewer has to click "show more." Links, key context, and your strongest pitch for the video should live in that first stretch — everything after it is there for viewers who are already engaged enough to expand the box.
The YouTube Description Checker flags exactly where that preview cutoff lands in your draft.
YouTube recommends a 1280×720 thumbnail at a 16:9 aspect ratio, with 640 pixels as an absolute minimum width. A thumbnail outside that ratio gets cropped unpredictably across different placements — search results, suggested videos, and the mobile app can all crop differently.
Upload any draft thumbnail to the Thumbnail Size Checker to confirm both the resolution and the aspect ratio before you set it live.
Beyond pre-publish checks, a few small utilities solve recurring annoyances: the YouTube Video ID Extractor and YouTube Channel ID Finder pull the underlying identifiers out of any URL format, the YouTube Timestamp Link Generator builds a direct link to a specific moment in a video, and the YouTube Thumbnail Downloader gives you direct links to a published video's thumbnail at every available resolution.
See a live search-result preview and get warned before your title gets cut off.
Check your description against the ~150-character preview cutoff and 5,000-character limit.
Turn a title or keyword list into a clean, comma-separated tag list under the 500-character limit.
Upload an image to check its dimensions and aspect ratio against YouTube's 1280×720 spec.
Get direct links to every resolution of a video's thumbnail image.
Pull the 11-character video ID out of any YouTube URL format.
Turn a video URL and a timestamp into a direct link that jumps to that moment.
Extract the handle, channel ID, or custom URL slug from any channel link.
No — the title and thumbnail checks matter most since they drive the click. Description and tag checks take seconds and are worth doing as a habit, but they carry less weight than getting the title and thumbnail right.