Musical Key Detection API for Harmonic Workflows

What Pulse returns

key root
major/minor scale estimate
key confidence
job status and selected-tool cost details

Example workflow

Ask Pulse for a free estimate, confirm the user has permission or lawful access, run key detection, then use the result as musical context rather than a guarantee; ambiguous, atonal, noisy, or short audio may need human verification.

Pricing and estimates

Estimates are free before paid analysis, and first-time users can try one short URL analysis before account setup. Pulse prices selected tools by audio duration using the same tool multipliers exposed by /tools: waveform 0.3 tokens/second, BPM 0.5 tokens/second, and key 0.5 tokens/second. The current token price is $0.005.

60 second key example30 tokens$0.15

3 minute full v1.0 suite234 tokens$1.17

Cached resultMay cost less$0.001 current cache-hit price

Examples are illustrative. The final estimate is shown before payment or API-key analysis and may account for selected tools, measured duration, cached analysis, failed tools, and checkout-path constraints.

Result guidance

Key detection is harmonic context, not a guarantee. Low-confidence, atonal, noisy, modulating, or very short audio should be checked by ear before committing catalog tags or DJ transitions.

For DJ planning, convert the detected key into your preferred harmonic-mixing notation, including Camelot-compatible labels, then use adjacent and relative keys as candidates rather than rules.

Pulse helps discovery and utility by making analysis explicit: result, confidence, selected tools, and job status. Human listening judgment remains the final check for release, performance, or catalog commitments.

Rights-aware analysis boundary

Pulse is designed for audio the user has rights, permission, lawful access, or another legal basis to submit. Agents and apps should confirm that before analysis. Pulse does not provide transcription, stem separation, mastering, loudness correction, chord transcription, or track structure segmentation in v1.0.

Pulse is designed to make audio analysis auditable. Each analysis flow should make clear which URL was submitted, which tools were selected, what the estimate was, when rights confirmation was given, and whether the job completed, partially completed, failed, or expired.