Record Sizes and Speeds: 7-Inch, 10-Inch and 12-Inch Records Explained
If you are buying a sleeve, a storage box or a first turntable, the first question is always the same: what size is the record? The answer decides which sleeve fits, which speed to select and what kind of music the format was built for. This guide explains the three standard diameters, the speeds that go with them, and how those choices came about.
A note on scope: this article is about the records themselves. Sleeve makers print the record size on their packaging, so use that label, and measure the sleeve you already own, rather than relying on a number from an article.
The three common sizes
Wikipedia's article on the gramophone record lists the common diameters as 12 in (300 mm), 10 in (250 mm) and 7 in (180 mm). It describes vinyl discs as most commonly 7-inch discs played at 45 rpm, and calls the 12-inch 33 1/3 rpm LP the most prevalent format today.
| Diameter | Usual speed | Typical use |
|---|---|---|
| 7 inch (180 mm) | 45 rpm | Singles |
| 10 inch (250 mm) | 33 1/3 rpm (LPs); 78 rpm (singles) | Early LPs and 78 rpm singles |
| 12 inch (300 mm) | 33 1/3 rpm (LPs); 45 rpm (maxi singles) | Albums, and longer singles |
The same article's table of standard formats lists 12-inch and 10-inch LPs at 33 1/3 rpm, 12-inch maxi singles at 45 rpm, and 7-inch singles at 45 rpm. It also notes that record sizes in the United States and the UK are generally measured in inches, and that 7-inch records are generally 45 rpm records.
The speeds
Records have been made at several rotational speeds. Wikipedia lists them as 8 1/3, 16 2/3, 33 1/3, 45 and 78 rpm. For everyday collecting you will meet three of them:
- 78 rpm. The Gramophone Company set 78 rpm as its recording standard in 1912, and by 1925 78 rpm was becoming standardized across the industry.
- 33 1/3 rpm. The speed of the LP.
- 45 rpm. The speed of the 7-inch single, and of 12-inch maxi singles.
When a turntable has a speed selector, the usual choices are 33 and 45, and some models also offer 78. Set the speed to match the record before you lower the stylus.
Why the LP arrived in 1948
Wikipedia's article on the LP record says that Columbia Records unveiled the LP at a press conference in the Waldorf Astoria on June 21, 1948. The name comes from "long playing" or "long play". The LP ran at 33 1/3 rpm and came in 12- or 10-inch diameters.
Columbia launched it in two sizes. The 10-inch matched the diameter of 78 rpm singles, and the 12-inch was the larger format. According to the article, the 12-inch format was at first reserved for higher-priced classical recordings and Broadway shows, while popular music stayed on 10-inch records. In the end the 12-inch 33 1/3 rpm LP prevailed as the dominant format for albums, and the 10-inch LP was discontinued by the mid-1950s. That is why most albums you find today are 12 inches.
Where the 7-inch 45 came from
RCA Victor released the first 45 rpm single, 7 inches in diameter with a large center hole. The LP article says the LP competed against the smaller 7-inch "45" or "single" format by RCA Victor, and that the LP eventually ended up on top as the album format. In practice, the two formats split the work: the 12-inch for albums, the 7-inch for singles.
The large center hole is easy to spot. Wikipedia's table of formats gives the original hole diameter for 45 rpm records as 0.504 in (12.8 mm). The same table gives 0.286 in (7.3 mm) for 33 1/3 and 78 rpm records, so the 45 hole is noticeably larger. Check your turntable's manual for how it is meant to handle 7-inch records.
What material are records made from?
The "vinyl" in "vinyl record" is shorthand for polyvinyl chloride (PVC). The gramophone record article says vinyl records made from PVC were introduced in 1948, and describes the pressing vinyl as a blend of polyvinyl chloride and polyvinyl acetate that has varied considerably over the years.
What this means for sleeves and storage
Sleeves are made for a particular diameter, so match the sleeve to the record:
- Identify the size first. Measure across the disc or read the format from the label or listing. If you know it is a 7-inch single, look for 7-inch sleeves.
- Use the label on the packaging. Sleeve makers state which record size their product fits. Treat that statement as the authority, and not an approximate figure from a guide.
- Keep different sizes apart. A 10-inch record in a 12-inch cover can slide around, and a 7-inch in a larger sleeve is likewise not held securely.
- Remember maxi singles. A 12-inch single plays at 45 rpm but uses a 12-inch sleeve, so do not guess the sleeve from the speed.
- Account for inner sleeves. If you are buying a protective sleeve for an album cover and the disc sleeve separately, see our guide to the types of record sleeves.
What this means for playing
- Speed: choose it by the record, not by the size alone. A 12-inch is usually 33 1/3, but a 12-inch maxi single is 45, so read the label.
- Center hole: 45s have a larger center hole than the other formats, so follow your turntable maker's instructions for 7-inch records.
- Older records: 78 rpm records are a different format from LPs and 45s, so only play them if your turntable's manual says it supports that speed.
Quick reference
- 7 inch: 45 rpm, singles, large center hole.
- 10 inch: the size of 78 rpm singles, and of the early LPs that were discontinued by the mid-1950s.
- 12 inch: 33 1/3 rpm LPs, the dominant album format, and 45 rpm maxi singles.
The takeaway
Size, speed and purpose line up in a few simple patterns. The 12-inch LP at 33 1/3 became the album, the 7-inch at 45 became the single, and the 10-inch is the older size that faded from albums by the mid-1950s. Knowing that makes it much easier to pick the right sleeve, the right speed and the right adapter for the record in your hand.
