Custom Mode in Suno, Explained: What Every Field Actually Does

Every guide on this site eventually says the same phrase: in Custom mode. This is the guide for the reader who hasn’t switched it on yet — what each field is for, how they divide the work, and which one to learn first. No production background needed; this is orientation, not technique.

The two modes

Suno’s default Simple mode takes one description — “a sad country song about my truck” — and makes every decision for you: lyrics, structure, style, voice. It’s genuinely good at producing a song. What it can’t do is produce your song, because you handed over every decision in one sentence.

Custom mode splits that sentence into separate controls. The moment you care about your own lyrics, a specific sound, or a chorus that lands where you want it, Custom mode is where you work. Everything on this site assumes it.

The Styles field: what the song sounds like

The Styles field holds a comma-separated description of the sound: genre, era, instruments, production character, mood, vocal type.

80s synth-pop, shimmering synth pads, punchy drums, breathy female vocals, dreamy nostalgic mood

It’s the highest-leverage box in the app, and it has a craft to it — what the model listens for, how many descriptors to use, what it quietly ignores. That craft is its own guide, the first real stop after this page.

The lyrics box: the words, and the map

The lyrics box does two jobs at once. The plain lines are the words that get sung. The lines in square brackets — [Verse 1], [Chorus], [Bridge] — are instructions that mark the song’s shape and never get sung.

[Verse 1]
These lines will be sung

[Chorus]
And these are the hook

One warning worth its own paragraph, because it’s the most common mistake in the whole app: parentheses get sung. Square brackets are instructions; anything in parentheses is treated as a performed lyric — that’s actually how you write background vocals like (ooh, ooh). Write (guitar solo) in the lyrics box and there’s a real chance someone sings the words “guitar solo” at you.

The tag vocabulary that works — and the honest news about tags being suggestions rather than commands — is covered in the structure tags guide.

Exclude Styles: what to keep out

The third field is the reverse of Styles: comma-separated terms for what you don’t want — the EDM drop that keeps invading your ballad, the banjo nobody requested. Leave it empty on a first generation; it’s a correction tool, not a starting one. When something uninvited shows up, the Exclude Styles cookbook has ready-made lists for the usual suspects.

The instrumental toggle

One switch, one job: no vocals. If you want an instrumental track, use the toggle rather than trying to prompt or exclude the vocals away — it’s the direct control, and the workarounds are less reliable.

Version and credits, briefly

A model picker sets which Suno version generates your song — paid plans run the current model (v5.5 as this is written), the free tier an older one — and each generation spends credits from your plan. Both of these are the most changeable facts on this page, so we’ll leave the details to Suno’s own pricing page and keep this guide about the fields, which have stayed stable across versions.

How the fields combine

The three text fields aren’t independent — they merge into one instruction, and they can contradict each other. Ask Styles for aggressive metal while your lyrics tags plead [Soft] [Acoustic], and the result averages into mush that serves nobody. The working principle across all of Suno: each field pulls in the same direction, and the fewer, clearer words win. Say what you want in Styles, shape where it happens with tags, forbid the specific invader in Exclude Styles.

And a calibration to carry into everything: all of these fields steer probabilities rather than issue commands. A perfect prompt raises the odds; it doesn’t sign a contract. That’s why the craft is iterative — generate, listen, diagnose before you spend the next credit.

Where to go from here

Learn the fields in the order they pay off: the Styles field first, structure tags second, exclusions when a problem shows up. Or take the whole path in order from Start Here — this page was step zero.