yes, and there is a backing track, and both of those things are true of every arena pop show you have ever been to.
the short answer
she sings the lead vocal live. the harmony stacks, doubles and ad-libs underneath it are played back from a track, which is how essentially every arena pop show with choreography works. on the wicked films she and cynthia erivo sang live on set rather than miming to a pre-recording, which is unusual for a film musical and was confirmed by the director.
what an arena vocal rig actually contains
three things, and the confusion comes from collapsing them into one. the lead vocal is a live microphone. the harmony stack — the four to twelve additional vocal parts that sit under every chorus on her records — is a playback, because there is one of her and there are twelve parts. and there is usually a low-level double of the lead, mixed underneath, to keep the sound consistent while somebody is moving.
none of that is a secret and none of it is unusual. it is how the shows work for every pop act operating at this scale with choreography, and it has been since the early nineties. the stacks are the specific reason it matters for her: her records are built on them more heavily than almost anybody's, so reproducing the arrangement without a track would mean either hiring twelve singers or performing a different song.
how to tell, if you want to
- listen for the breaths. a live lead has audible intake before phrases and a track does not. this is the single most reliable tell and it does not require good ears.
- listen at the end of long notes. a live sustain wobbles and decays unevenly. a recorded one holds.
- watch what happens when the choreography is hardest. a live vocal thins out and moves around during heavy movement. that is not a fault; it is evidence.
- ignore the harmony. it will be perfect every night in every venue, because it is the same file. that proves nothing about the lead on top of it.
the wicked recordings
the film half of the question has a straightforward answer. jon m. chu has said that both grande and cynthia erivo insisted on singing live on set rather than lip-syncing to a studio pre-record, and that the decision was immediate for both of them. film musicals overwhelmingly do it the other way, because live capture on a set is a technical nuisance for everybody involved.
why the accusation keeps recurring
partly because a clip of any singer at any moment can be made to look like anything, and partly because of a specific characteristic of her voice: she moves between a light head register and a heavy chest one very quickly, and on a phone speaker the transition can sound like an edit. it is not one.
there is also the speaking voice question, which is adjacent and gets bundled in. she has addressed that directly — that she switches register in conversation out of habit and for vocal health, and that the volume of scrutiny it attracted is not applied to men who do the same thing. that is a fair point and it is also, separately, just what a working singer does with their voice all day.
the short version
if you are asking whether the person on stage can sing: the answer is on any of the acoustic performances, of which there are many, with no track under them at all. the twenty best songs is a good place to start and the vocal piece is the technical one.
questions people ask
does ariana grande lip sync?
the lead vocal is sung live. the harmony stacks and doubles underneath it are played back, which is standard for every arena pop show with choreography.
did ariana grande sing live in wicked?
yes. director jon m. chu has said she and cynthia erivo both insisted on singing live on set rather than miming to a studio recording.
how can i tell if a vocal is live?
listen for breaths before phrases and for the wobble at the end of long notes. both are present in a live lead and absent from a track.
why does her voice change when she talks?
she has said she switches register out of habit and for vocal health, and has pointed out that the same thing in men attracts no comment.