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DIN 471 External Circlip Size Chart (Shaft Retaining Rings)

Guide · Updated October 28, 2026

An external circlip, or shaft retaining ring, is a spring steel ring that snaps into a groove on a shaft to stop a bearing, gear or spacer from sliding off. DIN 471 is the metric standard most shops buy from, and it sets both the ring and the groove you cut for it. The chart below covers the common 10 to 100 mm sizes. The ring thickness, groove diameter, groove width and edge distance agree between the RoyMech DIN 471 table, the maschinenbaurechner.de DIN 471 table and the Axial Supply DIN 471 reference (which runs to 30 mm). Groove depth is worked out from the shaft and groove diameters. DIN 471 was revised in May 2026, so check the current edition or your ring supplier for critical work.

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Step by step

Measure the shaft: Mike the shaft where the ring will sit. The DIN 471 size is the shaft diameter d1, not a size of the ring itself.
Read the groove: Find d1 in the chart and read the groove diameter d2, the groove width m and the ring thickness s.
Check edge distance: Keep at least n from the groove to the shaft end or any step, or the groove wall can shear out under load.
Cut the groove: Plunge with a grooving tool ground to m or a little under, then open to width. Hold d2 to its minus tolerance.
Break the edges: Keep the groove wall square and the outer corner sharp on the loaded side. Deburr only lightly so the ring bears fully.
Fit the ring: Spread it with external circlip pliers only as far as needed to pass over the shaft, then check it snaps fully into the groove.

DIN 471 ring and groove dimensions (mm)

Columns are: nominal shaft diameter d1, ring thickness s, groove diameter d2, minimum groove width m, groove depth t = (d1 − d2) / 2, and minimum distance n from the groove to the shaft end. Groove width m is held to H13, so it can be up to about 0.14 mm over the listed figure on small sizes and 0.25 mm on large ones. Groove diameter d2 is a minus tolerance: about −0.11 mm for 10 to 19 mm shafts, −0.13 for 20 to 23, −0.21 for 24 to 31, −0.25 for 32 to 50, −0.30 for 54 to 82 and −0.35 for 85 to 100 mm.

Shaft d1 | Ring thickness s | Groove dia d2 | Groove width m (min) | Groove depth t | Min edge distance n
10 | 1 | 9.6 | 1.1 | 0.20 | 0.6
12 | 1 | 11.5 | 1.1 | 0.25 | 0.8
14 | 1 | 13.4 | 1.1 | 0.30 | 0.9
15 | 1 | 14.3 | 1.1 | 0.35 | 1.1
16 | 1 | 15.2 | 1.1 | 0.40 | 1.2
17 | 1 | 16.2 | 1.1 | 0.40 | 1.2
18 | 1.2 | 17 | 1.3 | 0.50 | 1.5
20 | 1.2 | 19 | 1.3 | 0.50 | 1.5
22 | 1.2 | 21 | 1.3 | 0.50 | 1.5
24 | 1.2 | 22.9 | 1.3 | 0.55 | 1.7
25 | 1.2 | 23.9 | 1.3 | 0.55 | 1.7
26 | 1.2 | 24.9 | 1.3 | 0.55 | 1.7
28 | 1.5 | 26.6 | 1.6 | 0.70 | 2.1
30 | 1.5 | 28.6 | 1.6 | 0.70 | 2.1
32 | 1.5 | 30.3 | 1.6 | 0.85 | 2.6
34 | 1.5 | 32.3 | 1.6 | 0.85 | 2.6
35 | 1.5 | 33 | 1.6 | 1.00 | 3
36 | 1.75 | 34 | 1.85 | 1.00 | 3
38 | 1.75 | 36 | 1.85 | 1.00 | 3
40 | 1.75 | 37.5 | 1.85 | 1.25 | 3.8
42 | 1.75 | 39.5 | 1.85 | 1.25 | 3.8
45 | 1.75 | 42.5 | 1.85 | 1.25 | 3.8
48 | 1.75 | 45.5 | 1.85 | 1.25 | 3.8
50 | 2 | 47 | 2.15 | 1.50 | 4.5
52 | 2 | 49 | 2.15 | 1.50 | 4.5
55 | 2 | 52 | 2.15 | 1.50 | 4.5
58 | 2 | 55 | 2.15 | 1.50 | 4.5
60 | 2 | 57 | 2.15 | 1.50 | 4.5
62 | 2 | 59 | 2.15 | 1.50 | 4.5
65 | 2.5 | 62 | 2.65 | 1.50 | 4.5
68 | 2.5 | 65 | 2.65 | 1.50 | 4.5
70 | 2.5 | 67 | 2.65 | 1.50 | 4.5
72 | 2.5 | 69 | 2.65 | 1.50 | 4.5
75 | 2.5 | 72 | 2.65 | 1.50 | 4.5
78 | 2.5 | 75 | 2.65 | 1.50 | 4.5
80 | 2.5 | 76.5 | 2.65 | 1.75 | 5.3
85 | 3 | 81.5 | 3.15 | 1.75 | 5.3
90 | 3 | 86.5 | 3.15 | 1.75 | 5.3
95 | 3 | 91.5 | 3.15 | 1.75 | 5.3
100 | 3 | 96.5 | 3.15 | 1.75 | 5.3

How to read the chart

Ring thickness steps up in bands: 1.0 mm to a 17 mm shaft, 1.2 mm to 26, 1.5 mm to 35, 1.75 mm to 48, 2.0 mm to 62, 2.5 mm to 80 and 3.0 mm to 100. Groove width is always that thickness plus 0.1 to 0.15 mm. Groove depth grows slowly, from 0.2 mm on a 10 mm shaft to 1.75 mm on a 100 mm shaft. So a deeper groove does not mean more holding force on its own. What matters most is the edge distance n and how square the loaded groove wall is.

Sizes not in the list, such as 11, 13, 19 or 21 mm, exist in DIN 471 too but are less common. Buy the ring first and check the supplier's groove figure if you need an odd size.

Worked example: groove for a 25 mm bearing seat

A 6205 bearing sits on a 25 mm shaft and needs a ring on the outboard side. The chart gives s = 1.2 mm, d2 = 23.9 mm, m = 1.3 mm and n = 1.7 mm. Groove depth is (25 − 23.9) / 2 = 0.55 mm a side. Cut the groove to 23.79 to 23.90 mm diameter (−0.21 mm tolerance) and 1.30 to about 1.44 mm wide. The bearing is 15 mm wide, so the near wall of the groove sits 15.0 mm from the shoulder, plus a few hundredths if you want end float. Leave at least 1.7 mm of shaft past the groove.

Worked example: grooving tool for a 40 mm shaft

For 40 mm, s = 1.75, m = 1.85 and d2 = 37.5 mm, so the depth is 1.25 mm a side. A 1.85 mm wide insert would leave you at the bottom of the width tolerance, which is fine. If you only have a 1.5 mm insert, plunge to 37.5 mm, step over 0.35 mm and plunge again. On a manual lathe, zero the dial on the shaft, then feed in 1.25 mm on the radius (2.50 mm on a diameter dial).

Worked example: checking a groove

An old 30 mm shaft has a groove that mikes 28.5 mm with a 1.7 mm width. DIN 471 wants 28.6 mm minus up to 0.21, so 28.39 to 28.60. The 28.5 reading is in range. Width 1.7 mm is over the 1.6 minimum and within H13, so a standard 1.5 mm ring will fit. Check with a pin gage or the ring itself that it seats all the way round.

External vs internal rings

DIN 471 rings go on shafts and close in to grip the groove. DIN 472 rings go in bores and spring outward. They use different pliers: external pliers open the ring, internal pliers close it. For tighter loads or no room for pliers lugs, look at heavy type DIN 471 rings, E-clips (DIN 6799) or a nut and shoulder.

Common problems

Ring spins or is loose: the groove is too deep or the ring was over spread on fitting. Use a new ring and check d2.
Ring pops out under load: edge distance n is too small, or the groove corner is rounded. Recut with a square wall.
Ring will not seat: the groove is too narrow or has a burr. Check width with the ring or a feeler.
Bearing has end play: the groove is too far from the shoulder. Add a shim washer or recut it closer.

FAQ

What size circlip fits a 20 mm shaft?

A DIN 471 20 mm ring. It is 1.2 mm thick and needs a 19.0 mm groove 1.3 mm wide, with at least 1.5 mm from the groove to the shaft end.

How deep is a DIN 471 groove?

Depth t is half of shaft minus groove diameter. For a 25 mm shaft, (25 − 23.9) / 2 = 0.55 mm.

Why is the groove wider than the ring?

Width m is a minimum with an H13 tolerance, about 0.1 to 0.15 mm over ring thickness s, so the ring drops in without binding.

Is DIN 471 the same as ISO 464 or ASME?

No. DIN 471 is the metric shaft ring most catalogs stock. Inch rings to ASME B18.27 use different groove sizes, so do not swap them.

Pin and retaining-ring size charts

Picking a fastener to locate or retain a part? Compare the other pin and ring charts in this set:

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