Beyoncé · I Am… Sasha Fierce

Ego

Ego is in B flat minor at 77.9 beats per minute.

Tempo

78 BPM · Andantemedian of 127 analyses · 77.8–77.9 across the middle eight tenths

Key: B♭ minor5 flats · the key most of the analyses agreed on
Agreement: 98%share of analyses that agreed
Analyses: 127people who ran the extractor
One beat: 770.2milliseconds, 60,000 ÷ BPM
Tuning: 434.2Hz · -23 cents from A 440
Dynamics: 5.41dB the level wanders from its average
Loudness: 0.596Essentia's 0–1 scale, not dB
Danceability: 1.201Essentia's danceability, 0–3

Source: AcousticBrainz, dump of 2022-06-23 (CC0) · MusicBrainz core data, 2026-09-17 (CC0) · how each number is measured. Measured up to 23.06.2022 — AcousticBrainz stopped collecting in 2022, so nothing released after that date is here.

What the numbers say

127 independent analyses of this recording were submitted to AcousticBrainz. All but a handful of them — 98% — put it in B flat minor, a key signature of 5 flats. The tempo printed above is the median of the 127 readings; 98% of them land within 2% of it, and they barely differ at all.

At 77.9 BPM one beat lasts 770.2 milliseconds, so a sixteenth note is 192.6 ms and a dotted eighth 577.7 ms — the delay times for this recording. Counted half as fast it is 39 BPM, counted twice as fast 155.8. A score would mark that Andante, by the ranges this site uses.

The analyses put the reference pitch of the recording at 434.2 Hz, which is 23 cents below concert A at 440 Hz — the sort of drift a tape machine or a slightly different mastering leaves behind. That is a fact about this transfer of the music, not about how it was played.

The dynamic complexity of the recording measures 5.41 dB: that is how far the level wanders from its own average, so a small number means a loud, flat master and a large one means a recording that still breathes. Its average loudness is 0.596 on Essentia's 0-to-1 scale, which is not decibels and is not comparable to a streaming service's number.

10 other recordings here are in B flat minor; the ones listed below are the closest in tempo.

Beats per bar are not in this dataset. AcousticBrainz's analysis reports a tempo, a key and a loudness, and no time signature at all, so this page does not print one — a 4/4 here would be a guess dressed as a measurement.

Keys that fit with B♭ minor

Each of these differs from B♭ minor by at most one accidental, or shares its tonic. That is the whole of what a mixing wheel encodes; here the relations are named instead of numbered.

Delay times at 78 BPM

Note value	Beats	Milliseconds	Hertz
Whole note	4	3080.9	0.32
Half note	2	1540.4	0.65
Dotted quarter	1.5	1155.3	0.87
Quarter note (one beat)	1	770.2	1.3
Quarter triplet	0.667	513.5	1.95
Dotted eighth	0.75	577.7	1.73
Eighth note	0.5	385.1	2.6
Eighth triplet	0.333	256.7	3.9
Dotted sixteenth	0.375	288.8	3.46
Sixteenth note	0.25	192.6	5.19
Sixteenth triplet	0.167	128.4	7.79
Thirty-second note	0.125	96.3	10.39

Half time 39 BPM · double time 155.8 BPM. Every row is one beat (770.2 ms) times the fraction in the second column.

Closest in key and tempo

Recordings in B flat minor, ordered by how near their tempo is to 78 BPM. A calculation, not a recommendation.

All songs in B flat minor All songs at 78 BPM B♭ minor at 70–79 BPM Beyoncé

MusicBrainz collapses 2 recording ids into this one. Recording id 8e39c183-5a11-4371-85f1-7d5781b280f7.