Every practice tool in one side panel.
Your journal writes itself.

Tempo Kit (also written TempoKit) is a desktop browser extension for music practice. It keeps a metronome, chromatic tuner, drone, timers, video practice controls and an automatic practice journal beside the lesson or song you are learning. Core tools are free; advanced tools are available with Pro.

Install Tempo Kit in desktop Chrome, Edge, Brave or another compatible Chromium browser. It is not a standalone iPhone or Android app. The Firefox build is pending store approval for the 2.0 release; check the install links and changelog for availability.

No. Tempo Kit logs metronome, timer, and video practice automatically (date, minutes, tempo range, and video title) with no forms to fill in. Tags, ratings, notes, and manual entries are optional. Free covers the auto-log, tags, Today card, streak, and export; Pro adds history beyond 14 days, the full-year heatmap, tempo trends, and the monthly and yearly reviews. Weekly reviews are free.

Install Tempo Kit free, open the panel, and choose Try Pro free. That opens ExtensionPay's own page, which starts a 3-day trial on your email. Every Pro feature unlocks for those 3 days and returns to free after, with nothing charged unless you decide to subscribe. The trial starts inside the extension, not on this website, so install first.

It's an early-supporter thank-you: 30% off with the code FOUNDING30 at checkout, good until November 30, 2026. Enter it in the promo code field on the checkout page. If you choose a subscription, the discounted price continues on renewals while you keep it active.

Yes. The metronome (with 9 click sounds and a no-guilt daily practice streak), chromatic tuner, countdown timer, stopwatch, and the practice journal are free core tools, no account needed. The journal auto-logs your sessions, takes tags, ratings and notes, runs the Today plan, and exports to PDF or JSON without paying a cent. Pro unlocks video practice tools (speed, pitch, 5-band EQ, vocal reduce, A-B loop, BPM & key detection) for YouTube, Bilibili, your own files, and other standard web players when the site allows browser extension control, plus polyrhythm layering, unlimited saved presets, folder organization, and the deeper journal: history beyond 14 days, the year-at-a-glance heatmap, per-piece tempo trends, and the monthly & yearly reviews. Weekly reviews are free. Practice notes, set lists with quick preset switching, drag-to-reorder, and one-click export/import of libraries work on every plan too. Since 2.0, so do sheet music on presets (three extra sources per preset free, unlimited with Pro), Pomodoro, all 22 widgets in the side panel, 13 color themes, and one reps counter. The full-tab Dashboard, custom layouts, and unlimited custom tabs are Pro (Free gets one custom sidebar tab).

Video practice works with YouTube and Bilibili out of the box. They are the tested, supported sources. You can also practice with your own audio or video files in the Practice Player, or connect another standard web player/streaming site/social media site when the site allows browser extension control. Use one connected video at a time. You can also attach sheet music to a preset and open it on a saved page, or log your practice sessions in the Journal.

Speed-and-pitch extensions control playback, and Tempo Kit does that too: speed, transpose, A–B loop, EQ, vocal reduce, BPM and key detection. The difference is everything around the playback. A slider changes the song; Tempo Kit runs the session, with a full metronome (30–600 BPM, subdivisions, swing, polyrhythm, 9 click sounds), a chromatic tuner reading cents and Hz, a timer and stopwatch, and presets with set lists and notes that restore your whole setup in one click. Then it remembers: sessions log themselves, so months of practice turn into a history you can actually look back on. That's the part a playback extension isn't built for, because it would have to become a practice app first. If you just want to drop a song a step, a free slider is fine. If you practice most days, Tempo Kit replaces the looper, the metronome site, the tuner app, and the notes doc at once, and keeps the record of it on your own device.

Tempo Kit checks your ExtensionPay status when the extension opens and when you return from checkout. If Pro does not appear immediately, close and reopen the extension. If it still shows as free, open Settings and choose Restore Pro. ExtensionPay will ask for the purchase email on its own secure page.

Only when you press record. Practice recordings capture your microphone and, if you turn on the camera, video too. Preview and download are free; saving a take to the library requires Pro. Takes stay on your device and are never uploaded by Tempo Kit. The tuner uses your microphone for real-time pitch detection only, BPM detection analyses tab audio temporarily, and local files in the Practice Player are played on your device.

You may cancel your subscription at any time. Cancellation stops future renewals, but Pro access continues until the end of your current billing period. We generally do not provide prorated refunds for unused subscription time, but may issue refunds for duplicate charges, billing errors, or serious technical problems at our discretion. View our full Cancellation & Refunds Policy.

Your saved work stays yours. When Pro ends, your data stays on this device. Existing presets, recordings and custom sidebar pages remain available. Dashboard layouts stay saved, but require Pro to open. Free limits apply to new additions, journal history and Pro tools. Imports also follow Free limits: 3 presets, 1 folder and 1 custom sidebar page; importing new Dashboard pages requires Pro. An import that exceeds these limits is refused without changing your saved data. Export remains available, including complete backups with saved recordings. Local storage is not a cloud backup: export before uninstalling the extension or clearing browser data. Canceling renewal keeps Pro active until the end of your paid period.

Open Tempo Kit → Settings → Manage Subscription. This opens the subscription management page (powered by Stripe) where you can cancel. After cancellation, Pro access continues until the end of your paid billing period.