Ranking Mariah Carey’s studio albums from smallest to largest vocal range: a THREAD
Note: Remixes, unless released on an official studio album (not a compilation album), have not been included; bonus tracks featured on an international edition of a particular album, however, have been included (such as Heat, Runway, etc.).
15. Glitter (2001)

C3-G#5-C#6-C7 (4 Octaves)
14. Merry Christmas (1994)

B2-F#5-C6-C7 (4 Octaves & 1 Semitone)

Supposedly a G7 has been found in AIWFCIY in the far background (I can’t hear it nor have I found an isolated audio clip of it); if this is true, the range of this album would be 4 Octaves, 4 Tones.
13. Music Box (1993)

D3-G#5-Bb5-E7 (4 Octaves & 1 Tone)
12. Daydream (1995)

B2-F#5-C6-D7 (4 Octaves, 1 Tone & 1 Semitone
11. Mariah Carey (1990)

C#3-G#5-C6-F7 (4 Octaves, 2 Tones)

I’ve yet to find confirmation of the supposed B2s in Someday. Isolated audio of the background vocals in the bridge show no sign of any B2s; if there were B2s, however, the range would be 4 Octaves, 3 Tones.
Here’s the isolated audio of the background vocals in the bridge of Someday:
10. Merry Christmas II You (2010)

Bb2-G#5-E6-Eb7 (4 Octaves, 2 Tones & 1 Semitone)
6 (TIED). Rainbow (1999)

F2-F#5-Bb5-C7 (4 Octaves, 3 Tones & 1 Semitone)

Although some have claimed the F2 in Bliss to be an E2, it is in fact a F2.
6 (TIED). Charmbracelet (2002)

F2-A5-D6-C7 (4 Octaves, 3 Tones & 1 Semitone)
6 (TIED). E=MC² (2008)

A2-G5-D6-E7 (4 Octaves, 3 Tones & 1 Semitone)
6 (TIED). Memoirs Of An Imperfect Angel (2009)

G2-G5-Eb6-D7 (4 Octaves, 3 Tones & 1 Semitone)
4 (TIED). The Emancipation Of Mimi (2005)

G2-A5-E6-F#7 (4 Octaves, 5 Tones & 1 Semitone)
4 (TIED). Caution (2018)

F#2-E5-F6-F7 (4 Octaves, 5 Tones & 1 Semitone)

Despite being about 28 years into her career at the time of recording this album, the vocal range exhibited is just 1 Semitone short of a full 5 Octaves.
2 (TIED). Butterfly (1997)

A2-G5-B5-A7 (5 Octaves)

Some doubt the legitimacy of the A7 in Outside, questioning if it may be an instrument or overtones. However, the A7 is widely accepted as an intentional note.
The following YouTube video isolates and highlights the A7 whistle found during the climax of the song:
2 (TIED). Me. I Am Mariah... The Elusive Chanteuse (2014)

G#2-A5-E6-G#7 (5 Octaves)
1. Emotions (1991)

Bb2-G5-G5-B7 (5 Octaves, 1 Semitone)

The B7 can be found at the end of Can’t Let Go as an octave unison atop the B6 whistle.
Here is a YouTube video that isolates and highlights the whistles found at the end of Can’t Let Go, including the supposed B7:
Here’s another one:
And another one:
So there you go! I hope you enjoyed my thread; let me know if there’s any notes I may have missed!
Correction: There’s a D7 in You Got Me, therefore the range of Charmbracelet is actually 4 Octaves, 4 Tones & 1 Semitone, placing it higher than its peers (that now rank at TIED 7th).
You can follow @mariconcarey.
Tip: mention @twtextapp on a Twitter thread with the keyword “unroll” to get a link to it.

Latest Threads Unrolled: