HookGenius › Learn › Suno v6 vs v5.5
Suno replaced v5.5 with v6 on 9 September 2026. We ran an identical prompt through both the same day. The short version: the field limits did not change, your old prompts are not invalid, and v6 sounded better on vocal flow and delivery — but the difference that will actually affect your work is none of those. It is that v6's two takes of the same prompt can differ more than a deliberate prompt edit does. That breaks the way most people judge a prompt, and it is the part nobody else is publishing.
How we know any of this. Every number below was read off the live
composer on launch day — from the fields' own maxlength attributes and Suno's on-screen
counters — or measured on a generation we ran ourselves. Where we only have one comparison, we say so
and do not call it a benchmark. Where we have not tested something, it is not in the table.
| v5.5 | v6 | |
|---|---|---|
| Lyrics field | 5,000 characters | 5,000 — unchanged |
| Styles field | 1,000 characters | 1,000 — unchanged |
| Exclude Styles | present | 1,000 characters |
| Models offered | one | three — v6, v6-wild, v6-mini |
| Track length, our run | 2:42 and 2:47 | 3:08 and 3:16 |
| Your stored style prompt | as written | byte-identical — nothing rewritten |
| Track caption | echoes your style text | writes its own summary |
The track-length row is one generation on each model, not an average. Treat it as an observation, not a spec.
We set out to improve one weak verse. We changed a single section cue — swapping loose, behind-the-beat phrasing for tight on-the-beat articulation — held everything else byte-identical, and regenerated.
Then we listened to both takes Suno returns. The two takes of the same generation disagreed with each other more than the prompt change did. Same prompt, same settings, one generation, and you reach opposite conclusions about whether your edit worked depending on which take you happen to play first.
This is the practical difference between v5.5 and v6, and it has a direct consequence: if you judge a prompt edit on a single take, you are mostly measuring noise. The Variety control in More Options governs how far the two takes diverge — lower it when you want consistency between them. We have not measured its optimum setting and will not invent one.
Nothing dramatic. In order of how much time each will save you:
HookGenius writes the full lyrics and a Suno-tuned style prompt from a sentence of direction — inside v6's real 1,000-character style budget, with the structure and vocal detail that survive the variance described above. Five free credits, no card.
Try it free →On the one track we ran through both with a byte-identical style prompt, v6 was better on vocal flow and delivery. That is a single comparison and we will not dress it up as a benchmark. The more useful answer is that v6's take-to-take variance is large enough that judging either model on one generation is unreliable — listen to both takes before concluding anything.
Yes. The style field is still 1,000 characters and lyrics are still 5,000, and a prompt stored on v5.5 comes back byte-identical on v6. Nothing about your existing prompts is invalid. What changed is how much the output moves between two takes of the same prompt, which makes small prompt edits harder to evaluate.
Measured off the live composer on launch day, from the fields' own maxlength attributes and Suno's on-screen counters: lyrics 5,000 characters, Styles 1,000, Exclude Styles 1,000. The title field carries no maxlength. These are unchanged from v5.5.
Three models exposed in the v6 composer. We have measured the field limits they share and run a prompt through the default v6. We have not yet run controlled comparisons between the three, and we are not going to characterise them from their names.
Take-to-take variance on v6 is substantial. In our testing the gap between the two takes of one generation exceeded the effect of a deliberate prompt change we made on purpose. The Variety control in More Options governs how far the takes diverge; lower it when you want consistency.
v5 was retired alongside the v6 launch. If you have tracks or workflows that depended on it, the practical move is to re-run the prompt on v6 rather than try to reproduce v5's behaviour.
No. The principle that carried v5.5 carries v6: describe the record you want in specific, producible terms rather than listing genres. What v6 changes is the evaluation loop, not the writing.
Published 9 September 2026, the day v6 shipped. HookGenius is an independent tool and is not affiliated with, endorsed by, or sponsored by Suno. “Suno” is a trademark of its respective owner.