YouTube Waveform Looper

Create precise loop regions on videos for transcription, language study, and focused listening practice. A lightweight tool for anyone learning music, language or choreography from YouTube, Facebook and Instagram videos. It adds a compact waveform strip over the player so you can set, save and recall precise loops without ever leaving the page. What you can do: - Create a loop by dragging on the waveform, or press A/B to mark start and end at the exact playback position - Precise loop playback, with optional crossfade and near-zero boundary snapping to avoid audio clicks at the loop edges - Save as many named presets as you like per video, and recall any of them with one click - Export and import your presets as a JSON file, for backup or sharing - Zoom and scroll the waveform to fine-tune a loop down to the millisecond - Change playback speed (0.25x-1.25x) without losing your loop position - Drag the panel to dock it to any edge of the player, or keep it floating - Work from the keyboard: play/pause, toggle the loop, set loop start and end, nudge either edge, jump back to the loop start and clear the region, without touching the mouse - Drag the "Bookmark" link from the panel to your bookmarks bar to keep all the presets of a video in one click. Opening it later asks whether to merge them with, or replace, the ones you already have - Bookmarks made on Facebook now reopen the video's own page. - Preset bookmarks: opening a bookmark now asks whether to Merge the loops into the ones already saved for that video, or Replace all of them. - Handy gestures: double-click the Zoom slider to frame the current loop, double-click the Speed slider or its value to go back to 1.00x, click the waveform to move the playhead, drag the loop to move it or drag its edges to resize it, use the mouse wheel to scroll Keyboard shortcuts (Alt is Option on Mac) work also on Facebook and Instagram: - Alt+Space: play / pause - Alt+L: loop on / off - Alt+[ and Alt+]: set loop start / end (on non-US keyboards use the keys in the same position, or AltGr + the bracket key) - Alt+Left / Alt+Right: move the loop end earlier / later - Alt+Shift+Left / Alt+Shift+Right: move the loop start earlier / later - Alt+J: jump to the loop start - Alt+Backspace: clear the region Three global commands also work when the panel isn't focused (change them at chrome://extensions/shortcuts): - Alt+Shift+L: toggle the loop - Alt+Shift+A: set loop start to the current time - Alt+Shift+B: set loop end to the current time Works on: - YouTube (videos, clips, embedded players) - Facebook (videos, reels), optional, enable it from the extension's settings - Instagram (posts, reels), optional, enable it from the extension's settings Everything stays on your device: no data ever leaves your browser, no account needed. What's new in 0.4.0 Presets can be sorted by Name or Start: click a heading to sort ascending, again for descending, again to go back to your own order. The choice is remembered. Reorder presets by hand: drag the handle next to each preset, or focus it and press Alt+↑ / Alt+↓. Dragging from a sorted list keeps that order and returns to manual. Screen readers announce each move. The "?" guide lists the new shortcut. Press and hold a preset to rename it. Importing presets in merge mode keeps your existing order; new presets are added at the end.