Do BPM and key belong in an AI music prompt?

Yes, BPM (beats per minute) and musical key can belong in your AI music prompts. Adding these details gives the AI model more specific instructions, helping it generate music closer to your vision. However, the model interprets these as suggestions, not strict commands.

What are BPM and Key in Music?

BPM, or beats per minute, measures the tempo of a song. A higher BPM means a faster song, while a lower BPM means a slower song. For example, a dance track might be around 120-130 BPM, while a ballad could be 60-80 BPM.

Musical key refers to the central note and scale around which a piece of music is built. It defines the set of notes that sound harmonious together. For instance, a song in C Major will primarily use notes from the C Major scale. The key often influences the emotional feel of a song; major keys tend to sound brighter, and minor keys often sound more melancholic.

How Suno Uses BPM and Key in Prompts

When you include BPM and key in a Suno prompt, the underlying Lyria 3 model processes these as strong preferences. The model uses this information to guide its generation process. For example, if you ask for a song at 120 BPM in C Major, the model will aim to create a track with that tempo and harmonic structure.

However, AI music generation is probabilistic. This means the model does not always hit the exact BPM or key you specify. It might generate a track that is close to 120 BPM but not precisely 120. Similarly, it might adhere to the C Major scale generally but introduce notes outside of it for creative effect or to transition between sections. The same prompt can produce different results each time you run it.

Examples of Prompts Using BPM and Key

Here are some ways to include BPM and key in your Suno prompts:

A chill lo-fi track, 75 BPM, in A minor, with a gentle drum beat and warm synth pads.

An upbeat pop song, 128 BPM, in G Major, with driving bass and a catchy synth melody.

A dramatic orchestral piece, 90 BPM, in D minor, featuring strings, brass, and timpani.

A spooky electronic ambient track, 60 BPM, in E Phrygian, with swirling textures and deep drones.

Notice that you can specify the key (e.g., C Major, D minor) and the BPM as a number. You can also include other musical elements like instruments, genre, and mood to further refine your request.

What if I don't know the BPM or Key?

Do not worry if you are unsure about BPM or musical key. You do not have to include them in every prompt. Suno can generate excellent music from descriptive prompts that focus on genre, mood, instruments, and style. The model is designed to infer musical characteristics from broader descriptions.

For example, these prompts are also effective:

A melancholic piano ballad with a slow tempo and a reflective mood.

An energetic techno track for a late-night club, with a fast beat and pulsating synths.

A peaceful acoustic folk song featuring guitar and soft vocals.

In these cases, the model will choose appropriate BPMs and keys that fit the described genre and mood.

Limitations and Copyright

Suno uses Google's Lyria 3 models, but it cannot imitate specific real-world artists or copyrighted songs. Do not include artist names or song titles in your prompts. This is a hard technical and legal limit.

Every track generated by Suno includes an inaudible SynthID watermark. This watermark helps identify the track as AI-generated.

The question of copyright ownership for AI-generated music is unsettled and varies by country. For example, the U.S. Copyright Office has stated it will not register works that lack human authorship. Check the copyright laws in your region for the most current information. Suno does not grant commercial usage rights with its free plan. A paid plan is required for commercial use; refer to the Suno terms of service for details.

Experiment with including BPM and key in your prompts to see how they influence the generated music. Remember that the model interprets these as suggestions, offering a balance between specific control and creative freedom.