Bar / measure duration
API · /tempo-api
Tempo & BPM API
healthy
3,054 Subscribers
Musical timing maths as an API — turn a tempo into exact times. The durations endpoint gives the length of every note value (whole down to sixty-fourth, plus dotted and triplet variants) at a given BPM, in milliseconds, in hertz, and in samples at your sample rate. The delay endpoint is the producer's note-to-millisecond tool: the delay and reverb times for 1/1 to 1/32 (straight, dotted and triplet) so time-based effects lock to the tempo. The bar endpoint gives the duration of a bar for any time signature. The convert endpoint turns BPM into milliseconds per beat (and back) and names the Italian tempo marking — Largo, Adagio, Andante, Moderato, Allegro, Presto and the rest. Everything is computed locally and deterministically, so it is instant and private. Ideal for DAWs and music-production tools, drum machines and sequencers, delay and echo plug-ins, metronomes, and audio apps. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 4 endpoints. This is tempo and rhythm timing; for notes, intervals, chords and scales use a music-theory API.
api.oanor.com/tempo-api
API health
healthy- Uptime
- 100.00%
- Server probes · 24h
- Avg latency
- 74 ms
- Server probes · 24h
- Subscribers
- 3,054
- active
- Total calls
- 100
- last 7 days
Pricing
Pick a tier — billed monthly, cancel anytime.
Free
Free
- 7,735 calls / month
- 2 requests / second
- Hard cap (429 above quota, no overage)
- 7,735 calls/month
- 2 req/sec
- Durations + delay + bar + convert
- No credit card
Starter
€9.25 /month
- 17,250 calls / month
- 8 requests / second
- Hard cap (429 above quota, no overage)
- 17.25k calls/month
- 8 req/sec
- ms / Hz / samples
- Email support
Pro
€29.15 /month
- 223,500 calls / month
- 20 requests / second
- Hard cap (429 above quota, no overage)
- 223.5k calls/month
- 20 req/sec
- DAW / plug-in pipelines
- Priority support
Mega
€67.15 /month
- 1,160,000 calls / month
- 50 requests / second
- Hard cap (429 above quota, no overage)
- 1.16M calls/month
- 50 req/sec
- Platform scale
- Dedicated SLA
Built by
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api.oanor.com/audius-api
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api.oanor.com/mixcloud-api
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api.oanor.com/vinyl-api
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api.oanor.com/helmholtz-api
Frequently asked questions
Quick answers about pricing, quotas, and integration.
How do I get an API key for Tempo & BPM API?
Sign up for free at oanor.com, generate an API key from the developer dashboard, and call Tempo & BPM API with the x-oanor-key header. No credit card needed for the free tier.
What's the rate limit for Tempo & BPM API?
Free tier allows 1 request per second. Paid plans scale up to 50 requests per second on the Mega tier. Hard limits return HTTP 429 above the quota — no surprise overage charges.
How much does Tempo & BPM API cost?
Tempo & BPM API has a free tier with 100 calls / month. Paid plans start at €9.25 / month with higher quotas and faster rate limits.
Can I cancel my subscription anytime?
Yes. Plans are billed monthly and you can cancel anytime from your billing dashboard. No long-term contracts and no cancellation fee.
Is Tempo & BPM API GDPR-compliant?
All requests to Tempo & BPM API go through our EU-based gateway. Your upstream API key never leaves our server and no personal data is shared with the upstream provider beyond the request you send.
Pick an endpoint from the list on the left to see its details and try it.
Code snippets
Sign up to get an API key, then call any path under your slug.
curl https://api.oanor.com/tempo-api/SOME_PATH \
-H "x-oanor-key: oanor_test_..."const res = await fetch("https://api.oanor.com/tempo-api/SOME_PATH", {
headers: { "x-oanor-key": "oanor_test_..." }
});
const data = await res.json();$ch = curl_init("https://api.oanor.com/tempo-api/SOME_PATH");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, ["x-oanor-key: oanor_test_..."]);
$response = curl_exec($ch);import requests
r = requests.get(
"https://api.oanor.com/tempo-api/SOME_PATH",
headers={"x-oanor-key": "oanor_test_..."},
)
print(r.json())Ratings
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