One of the most common questions for new vinyl collectors is how to tell whether a record should be played at 33⅓ RPM or 45 RPM. Playing a record at the wrong speed can make music sound too slow, too fast, or completely distorted—so knowing how to check is essential for protecting your listening experience and your equipment.
Here’s a clear, practical guide to identifying record speeds quickly and accurately.
1. Check the Label — Most Records Are Marked
The easiest way to identify speed is to look at the center label.
Manufacturers typically print the playback speed directly on it, shown as:
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33⅓ RPM
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45 RPM
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Occasionally 78 RPM for vintage shellac records
If you see the number printed on the label, you’re done. But if you don’t (and many older or independent releases omit it), use the next methods below.
2. Look at the Record Size
While not always perfect, record size often hints at speed:
| Size | Typical Speed | Notes |
|---|---|---|
| 12-inch | Mostly 33⅓ RPM | Standard LP albums |
| 12-inch singles | Sometimes 45 RPM | Usually high-quality dance/club releases |
| 7-inch | Mostly 45 RPM | Common for singles |
| 10-inch | Could be 33⅓ or 45 | Mixed formats—check label or runout |
Remember: Size alone is not definitive, but it gives a strong clue.
3. Inspect the Groove Spacing
Groove patterns reveal a lot:
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33⅓ RPM records
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Typically have narrow, tightly-packed grooves.
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Designed for longer play time.
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45 RPM records
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Grooves are wider and more spaced out.
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Used for better audio dynamics at shorter durations.
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If the grooves look thick and the spacing looks looser, there’s a good chance it’s a 45.
4. Check the Runout (Deadwax) Engraving
The “deadwax” is the smooth area near the label. Many pressing plants engrave codes here.
Look for clues such as:
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“45”, “33”, or “33⅓”
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Catalog number variations that correspond to speed
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Indications like “LP” (usually 33⅓) or “SINGLE” (often 45)
This method takes a bit of knowledge, but once you get used to reading runout markings, it’s very reliable.
5. Watch the Rotation (If You Already Tried Playing It)
If you accidentally start the record on the wrong speed, the music will clearly tell you:
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Too slow / deep and sluggish → You’re playing a 45 at 33⅓
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Too fast / chipmunk-like → You’re playing a 33⅓ at 45
This method shouldn’t be your first choice, but it’s a quick sanity check.
6. Know the Typical Formats
Understanding common standards helps a lot:
Most 33⅓ RPM records:
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Full-length LP albums (12-inch)
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Long EPs or deluxe reissues
Most 45 RPM records:
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7-inch singles
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Audiophile 12-inch releases (high-fidelity mastering)
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Some limited editions or remasters
If you know the format, speed becomes easier to guess.
Why Playback Speed Matters
Using the correct RPM ensures:
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Accurate pitch and timing
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Optimal audio fidelity
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Reduced stylus wear
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Protection of your turntable’s motor and components
A simple mistake can make a great record sound terrible—so it’s worth taking the time to check.
Final Tip: When in Doubt, Start at 33⅓
If you can’t determine the speed from any of the methods above, start the record at 33⅓ RPM and adjust based on how it sounds. This is the safer default for most modern LPs.
Now you know exactly how to identify whether a record is 33 or 45—quickly, accurately, and confidently. Happy spinning!