Metric for macOS

A windowed timing and frequency toolkit for macOS, now with a built-in metronome. Whether you're keeping time, setting delay times in a mix, tuning an FM patch, syncing an LFO, or transposing a sample, Metric gives you instant, precise answers all in one clean, sidebar-navigated app that sits alongside your DAW. Now with Siri, Shortcuts, and a Notification Center widget.

Metronome with tap tempo & visual beats
BPM → ms / Hz converter (straight, dotted, triplet)
Note ↔ Frequency table (108 notes, tuning-aware)
Transpose & Speed, FM Calculator, LFO Rates, 32 Harmonics
Siri, Shortcuts & a Notification Center BPM widget

Screenshots

Includes light and dark screenshots that follow the website theme.

Tap and measure tempo. Instant and averaged BPM with one click.

Tap Tempo screen on macOS — Tap and measure tempo. Instant and averaged BPM with one click.

Save and recall tempo presets. Keep your favourite BPMs one click away.

Tap Tempo preset screen on macOS — Save and recall tempo presets. Keep your favourite BPMs one click away.

Convert BPM to ms and Hz. Straight, dotted, and triplet values at a glance.

BPM to ms/Hz table on macOS — Convert BPM to ms and Hz. Straight, dotted, and triplet values at a glance.

Look up any note's frequency. 108 notes with Hz, MIDI, period, and sample counts.

Note to Frequency converter on macOS — Look up any note's frequency. 108 notes with Hz, MIDI, period, and sample counts.

Transpose keys and speed. Semitone shift, interval name, and new tempo instantly.

Transpose and Speed helper on macOS — Transpose keys and speed. Semitone shift, interval name, and new tempo instantly.

Design FM timbres by the numbers. Ratios, sidebands, and pitch correction in one view.

FM Calculator on macOS — Design FM timbres by the numbers. Ratios, sidebands, and pitch correction in one view.

Sync your LFO to the beat. 17 divisions from 4 bars to 1/32 triplets.

LFO Rate calculator on macOS — Sync your LFO to the beat. 17 divisions from 4 bars to 1/32 triplets.

Explore the harmonic series. 32 harmonics with frequencies, notes, and intervals.

Harmonic Series explorer on macOS — Explore the harmonic series. 32 harmonics with frequencies, notes, and intervals.

Keep perfect time. A precise metronome with visual beats and live transport.

Metronome on macOS — Keep perfect time. A precise metronome with visual beats and live transport.

Your tempo in Notification Center. Siri, Shortcuts, and a BPM widget keep your metronome a glance away.

Widget, Siri, and Shortcuts on macOS — Your tempo in Notification Center. Siri, Shortcuts, and a BPM widget keep your metronome a glance away.

Fine-tune your setup. Adjust A4 tuning, sample rate, and preferences.

Settings screen on macOS — Fine-tune your setup. Adjust A4 tuning, sample rate, and preferences.

Features

Metronome: A precise metronome with a tempo dial, tap-to-set tempo, time signatures and subdivisions, and a clear visual beat indicator.
Tap Tempo: Click the large tap target to measure tempo. See instant BPM from your last tap and a rolling average over up to eight taps. Send either reading straight into the BPM Converter, Transpose, or LFO Rate tools with a single click. Your tempo flows across every tool automatically.
BPM → ms / Hz Converter: Enter a tempo and read straight, dotted, and triplet values for whole, half, quarter, eighth, and sixteenth notes. Every row shows milliseconds and frequency in Hz, so you can dial in delay, reverb pre-delay, or sidechain timing without reaching for a calculator.
Note Frequency Table: Browse all 108 chromatic notes from C0 to B8. Each note shows its MIDI number, frequency in Hz, period in milliseconds, and sample counts at 44.1 kHz, 48 kHz, and 96 kHz. Middle C is flagged for quick reference. Based on A4 = 440 Hz.
Transpose & Speed: Pick an original key and a target key to see the semitone shift, interval name, and exact DAW transpose value. Add an original BPM and Metric computes the new tempo and playback speed ratio. Fine-tune with a cents slider (±100) and a speed slider spanning two full octaves (±24 semitones).
FM Calculator: Ratio Explorer lets you set carrier and modulator ratios with a base frequency and choose from ten classic FM presets, from hollow octaves (1:1) to inharmonic bells (1:π). Pitch Correction mode works in reverse: pick a target note and get the exact carrier and modulator frequencies. Both modes show a sideband table with up to ten partials, their frequencies, nearest notes, and colour-coded amplitudes driven by a modulation index slider.
LFO Rate Calculator: Convert any BPM into LFO rates across 17 musical divisions, from four bars down to 1/32 triplets. Each row displays Hz, period in milliseconds, and samples per cycle at 44.1 kHz, 48 kHz, and 96 kHz. Reverse lookup lets you enter any Hz value and find the closest matching musical division, with the error clearly shown.
Harmonic Series Explorer: Start from a frequency or pick any note and see the first 32 harmonics listed with frequency, nearest note name, cents deviation, and interval label. Low-order harmonics are colour-coded for easy identification. Deviations greater than 30 cents are highlighted so you can spot inharmonic content at a glance.

Tools That Talk to Each Other

Tap a tempo once and it appears everywhere: BPM Converter, Transpose, and LFO Rate all share the same live BPM. Note Frequency, FM Calculator, and Harmonics all stay consistent at A4 = 440 Hz.

Siri, Shortcuts & Widget

Drive Metric hands-free. Ask Siri to start or stop the metronome, set a BPM, tap a tempo, convert BPM to ms, find a note frequency, or transpose a tempo. Every tool is a Shortcuts action too, and the BPM widget keeps your tempo in Notification Center.

Built for Your Desktop

Runs entirely offline no account, no ads, no tracking
Native macOS app with sidebar navigation
Dark-mode aware interface that follows your system appearance
Three industry-standard sample rates: 44.1 kHz, 48 kHz, and 96 kHz
Resizable window keep it open beside your DAW

Whether you're a producer programming delays, a sound designer sculpting FM timbres, a synth player tuning oscillators, or an audio engineer checking frequencies, Metric puts every timing and frequency answer on your desktop.