Why does 45 RPM sound better than 33⅓ RPM?

At 45 RPM the groove velocity is higher, meaning more vinyl passes under the stylus per second. This allows wider groove modulation, better high-frequency response, greater dynamic range and less inner-groove distortion. The trade-off is shorter playing time per side.

What causes inner-groove distortion?

As the stylus moves towards the centre of the record, the linear velocity decreases. This means the same audio frequency is encoded in a shorter physical space, making it harder for the stylus to track accurately. Inner grooves can have up to 50% less velocity than outer grooves.

How much music can fit on a 12-inch vinyl?

A standard 12-inch LP at 33⅓ RPM can hold about 22 minutes per side with good audio quality. Pushing beyond 25 minutes requires narrower grooves, which reduces volume and bass response. A 12-inch single at 45 RPM typically holds 10-12 minutes per side.

What is groove spacing?

Groove spacing (or pitch) is the distance between adjacent grooves on the record. Wider spacing allows louder cuts with more bass, while narrower spacing fits more playing time. Typical spacing ranges from 0.1mm (long playing) to 0.3mm (loud cuts).

AudioCalcs

Vinyl RPM Calculator — Playing Time & Groove Spacing

Calculate playing time, groove spacing and linear velocity for vinyl records.

Record Size

Speed

Playing Time (per side)

How We Calculate This

Groove Spacing

Spacing = (outer radius - inner radius) / (RPM × playing time)

Linear Velocity

Velocity = 2π × radius × RPM / 60 (in cm/s)

The outer edge of a 12-inch LP at 33⅓ RPM moves at about 51 cm/s. The inner groove at about 20 cm/s — less than half the speed, which is why audio quality degrades towards the centre.

Total Groove Length

Length = 2π × average radius × total revolutions

Frequently Asked Questions

Related Calculators

BPM Sync Calculator

Calculate the pitch adjustment percentage needed to sync two tracks at different BPMs. Essential for DJs performing seamless beatmatching.

Harmonic Mixing Calculator

Find compatible keys for harmonic mixing using the Camelot wheel system. Essential tool for DJs creating seamless musical transitions.

Loop Length Calculator

Calculate loop length in milliseconds and samples from BPM and bar count. Essential tool for precise looping in DAWs and samplers.

Delay Time Calculator

Calculate delay times in milliseconds synced to BPM for all note values including dotted and triplet divisions. Free producer tool.

LFO Rate Calculator

Calculate LFO rate in Hz synced to your BPM for all note divisions including dotted and triplet values. Free online producer tool.

Last updated: February 2026

All calculations are estimates based on standard formulas. Always verify results for critical applications.