You are looking at index.html opened directly. Nothing here can work, because opened this way it has no connection to Chrome.
ScreenCap has to be installed. It takes about a minute and needs no command line:
chrome://extensions into the address bar and press Enter.ScreenCap folder — the one with manifest.json inside it.After that you never open this file again. Browse to any page, click the ScreenCap icon, and this panel appears floating over that page, ready to record it.
This panel closes whenever you click outside it. That cancels nothing — a recording in progress keeps running, and clicking the ScreenCap icon brings the panel back.
Ready
The tab you are looking at when you click the ScreenCap icon. There is no field for a web address, because ScreenCap films the live tab rather than loading a copy of the page inside itself.
So the order is: browse to the page, then open ScreenCap. The panel at the top of the record screen names the page it is about to film. If that is not the right one, close the popup, switch tabs, and click the icon again.
Only the tab in front of you can be recorded. A background tab is not being drawn by the browser, so there would be nothing to capture.
ScreenCap subfolder.The video is whatever the tab shows, so the window shape decides the video shape. Match window to format resizes the browser to the aspect ratio the platform wants, and the readout tells you what you will actually get before you commit to a take.
Two things affect whether you reach the full 1080-pixel spec. A high-DPI screen captures at twice the layout size, so a 540 by 960 viewport already records at 1080 by 1920. And a tall vertical format needs a tall window, which a short desktop screen may not have room for. When the window cannot reach the spec, the readout says so and gives you the real number.
Scale output to the exact spec size resamples the capture to the platform's exact pixel dimensions. It does not add detail that was not captured, but it does produce a file that matches the spec sheet, which some upload flows prefer. If the window shape does not match the format, the page is fitted inside the frame with bars rather than cropped.
Resizing the window to a narrow shape usually makes the site render its mobile layout, which is normally what you want for a vertical post. Reload after resizing if the page does not reflow on its own.
Speed is page pixels per second. Around 150 reads comfortably for text; 300 to 500 suits a fast marketing sweep. The estimated length under the controls updates as you change it.
Curve decides whether the scroll starts and stops gently or runs flat the whole way. Glide looks better alone; constant rate cuts together more predictably with other clips.
Hold at top and end give you still frames to trim against.
Wake lazy images runs a fast invisible pass down the page and back before recording, so images that load on scroll are already there. Turn it off if a page animates on entry and you want those animations on camera.
Two switches, independent of each other. My voice records the microphone, for narrating over a take. Browser audio records what the page itself plays. Turn on either, both, or neither — with both on they are mixed into a single track, and with both off the recording is silent.
The first time you pick anything involving the microphone, ScreenCap opens a page to ask Chrome for access. That page exists because Chrome only raises a microphone prompt on something visible, and the part of the extension that does the recording is not. Granting it once covers every recording after that. The page shows a level meter so you can confirm the right input is live before you commit to a take.
Tab audio keeps playing through your speakers while it is captured. Without that it would go silent for you, which makes narrating over a video impossible to time.
If the microphone turns out to be unavailable when a take starts, the recording continues without narration rather than failing, and says so afterwards. Worth checking the level meter first on anything you cannot easily reshoot.
File name sets the front of the name; the date and time are always appended. Call something growthpaths-home and you get growthpaths-home-20260904-143022.mp4. The stamp means nothing overwrites anything, and sorting a folder by name groups every take of the same thing together in the order you made them.
Tick Ask for a name before each recording and ScreenCap asks each time, with the last name filled in ready to edit. Better when you are recording several different things in one sitting.
Save to names a subfolder of Downloads. Leave it empty to drop files straight into Downloads.
Browse hands the save over to Chrome's own dialog, which opens when the recording finishes and can reach any folder on your machine. It is the only way out of Downloads: Chrome does not let an extension write anywhere else, and offers no folder picker of its own. The trade is that every take then needs a click to complete, so it suits the occasional recording that has to land in a project folder rather than everyday use.
Format lists only what your Chrome can actually encode. Pick MP4 with H.264 when it is offered — Instagram, TikTok, Facebook and YouTube all take it directly. WebM uploads to some of them but not all, and converting afterwards costs a re-encode.
Switch the mode at the top of the record screen to Record what I do and ScreenCap stops driving the page. It captures the tab while you click, type and scroll by hand — for walkthroughs, bug reports, and anything the auto-scroll cannot stage.
Press Start record and a countdown fills the tab. It clears before the recorder starts, so it never lands in the video. Three seconds is the default; set it to zero to begin immediately.
The popup closes the moment you click into the page, which is the point — you need your hands on the tab. While a take is running the ScreenCap icon carries a red REC badge. That badge is browser chrome, not page content, so it stays out of the recording.
There are four ways, and they fail in different situations, which is why there is more than one.
Alt+Shift+S, anywhere in Chrome. The reliable one. It is a browser-level shortcut, so it works whatever has focus — the page, the address bar, a different tab, a different window — and it keeps working after the recorded page navigates. Use this one by default. Change it at chrome://extensions/shortcuts, or with the Change button on the record screen.
Your stop key, or Escape, inside the recorded tab. Convenient while your hands are already on the page. These are page-level listeners, so they only fire when the page itself has keyboard focus, only in the tab being recorded, and they stop working if that page navigates somewhere else.
The Stop button. Click the ScreenCap icon and press Stop. Always available.
The time limit. A take stops on its own after the number of minutes set under Session. Set it to 0 to remove the ceiling, though leaving some limit means a recording you walk away from cannot run indefinitely.
Whatever you choose as the stop key stops reaching the page for the duration of the take, which is why Ctrl+C means no copying on camera.
A scrolling page is the hardest thing there is to encode: every pixel changes on every frame, so there is nothing for the codec to reuse between them. Three settings decide how smooth the result looks.
Frame rate. 60 fps is the default because scrolling is continuous motion. 30 is what the platforms nominally ask for and is fine for talking heads, but it shows every step in a scroll.
Speed against frame rate. If the page advances less than one pixel per captured frame, it visibly stalls and jumps rather than gliding. At 30 fps that happens below 30 px/s; at 60 fps, below 60. The note under the speed slider warns you when your settings fall in that range. Slow scrolls need the higher frame rate.
Quality. Full-frame motion eats bitrate. Good is enough for a slow crawl over mostly text; a fast sweep over photographs wants Max, or the codec smears and the motion reads as stuttering even when every frame is present.
Pause the page's own animations stops carousels, marquees and looping video from competing for frames while the scroll is running. Turn it off when those animations are the point of the recording.
Short-form feeds reward short videos. Somewhere under 90 seconds is a safe target across Reels, TikTok and Shorts, well inside every current cap. Platform maximums move around, so check the destination if you are pushing past a few minutes.
Chrome blocks tab capture on its own pages, so chrome:// tabs, the Web Store and the extensions page cannot be recorded. Some pages scroll an inner container rather than the document itself; ScreenCap drives the document, so those pages stay still. Test scroll will show you before you waste a take.
ScreenCap folder and unzip it somewhere permanent. Chrome loads it from this location every time it starts, so do not put it in a temporary folder.chrome://extensions.ScreenCap folder itself — the one holding manifest.json, not the folder above it.Updating. Replace the folder contents with the new version, then press the reload arrow on the ScreenCap card at chrome://extensions. Chrome does not pick up changed files on its own.
If something looks broken after an update, it is usually a file that did not get copied across. Check for errors on the ScreenCap card, and confirm the folder still has manifest.json, index.html, and the js, css and icons folders inside it.
The four-step guide on the record screen is hidden once you dismiss it.
ScreenCap/, MP4 where Chrome supports it and WebM otherwise.