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G7 Tolerance Chart (Hole G7)

Upper and lower deviations of hole G7 for nominal sizes 0–500 mm, per ISO 286-1. Values in mm; "+" means larger than nominal, "-" smaller. Calculate other sizes →

Nominal size (mm)Upper deviationLower deviationTolerance (IT)
0 ~ 3+0.012+0.0020.010
>3 ~ 6+0.016+0.0040.012
>6 ~ 10+0.020+0.0050.015
>10 ~ 18+0.024+0.0060.018
>18 ~ 30+0.028+0.0070.021
>30 ~ 50+0.034+0.0090.025
>50 ~ 80+0.040+0.0100.030
>80 ~ 120+0.047+0.0120.035
>120 ~ 180+0.054+0.0140.040
>180 ~ 250+0.061+0.0150.046
>250 ~ 315+0.069+0.0170.052
>315 ~ 400+0.075+0.0180.057
>400 ~ 500+0.083+0.0200.063

Each row applies to the whole size range shown. Ranges are "over the first value, up to and including the second".

How to read G7

G7 is an ISO 286 tolerance class. The uppercase letter G is the fundamental deviation (which side of the nominal size the tolerance zone lies on), and the number 7 is the tolerance grade IT7 (how wide the zone is). Sliding (very small clearance): G7/h6 is the precision sliding fit on the shaft-basis system: slides freely with almost no play. Guide bushings, precision slides. Typical processes for IT7: fine turning, reaming, fine boring: the usual grade for fitted holes (H7) and h7 dowel pins.

On a drawing or in a specification, Ø6 G7 and 6(+0.016/+0.004) mean the same thing — the second form writes the deviations out, so nobody has to look them up. SFP product specifications always use the second form.

Quick lookup for common sizes

Click "Calc" in the last column to open the calculator, where the written-out form can be copied with one click.

SizeUpper deviationLower deviationActual limits (mm)
Ø1+0.012+0.0021.002 ~ 1.012Calc
Ø1.5+0.012+0.0021.502 ~ 1.512Calc
Ø2+0.012+0.0022.002 ~ 2.012Calc
Ø2.5+0.012+0.0022.502 ~ 2.512Calc
Ø3+0.012+0.0023.002 ~ 3.012Calc
Ø4+0.016+0.0044.004 ~ 4.016Calc
Ø5+0.016+0.0045.004 ~ 5.016Calc
Ø6+0.016+0.0046.004 ~ 6.016Calc
Ø8+0.020+0.0058.005 ~ 8.020Calc
Ø10+0.020+0.00510.005 ~ 10.020Calc
Ø12+0.024+0.00612.006 ~ 12.024Calc
Ø13+0.024+0.00613.006 ~ 13.024Calc
Ø16+0.024+0.00616.006 ~ 16.024Calc
Ø20+0.028+0.00720.007 ~ 20.028Calc
Ø25+0.028+0.00725.007 ~ 25.028Calc
Ø30+0.028+0.00730.007 ~ 30.028Calc
Ø35+0.034+0.00935.009 ~ 35.034Calc
Ø40+0.034+0.00940.009 ~ 40.034Calc
Ø50+0.034+0.00950.009 ~ 50.034Calc
Ø60+0.040+0.01060.010 ~ 60.040Calc
Ø80+0.040+0.01080.010 ~ 80.040Calc
Ø100+0.047+0.012100.012 ~ 100.047Calc

Common fits

FitTypeTypical use
G7/h6ClearancePrecision sliding fit on the shaft-basis system, equivalent to H7/g6. Use G7 for the hole when the shaft is a standard part (h6 ground shafting, dowel pins).

Alternative classes (tighter)

The tolerance zones of the classes below lie entirely inside G7 (true for every size range from 0 to 500 mm), so they also satisfy a drawing that calls for G7. Those listed first are closest to G7; price and lead time still depend on material, size and stock.

G6G5

Related tolerance charts

FAQ

How big is G7 exactly?

It depends on the diameter. For Ø6, G7 means the part must measure between 6.004 and 6.016 mm, written 6(+0.016/+0.004). For other diameters see the chart above; every size range is listed.

Is G7 a hole tolerance or a shaft tolerance?

Letters in uppercase denote a hole (inside diameter). In lowercase, g7 is a shaft tolerance, lying on the opposite side of the nominal size.

The drawing calls for G7 but the parts I have are G6. Can I use them?

Yes. G6 is tighter than G7: at every diameter its limits fall inside the range G7 allows. The precision is simply higher than required, so the price may be a little higher.

Tell us the tolerance on your drawing and we will match it to stock. Write the size as 8(0/-0.015) or 8h7 and e-mail it with material, length and quantity to sfp@sfp-tw.com, or check availability directly in the online catalog. Stock dowel pins come in h6 / h7 / m6 as well as minus and plus tolerance; whenever the tolerance zone of a stock part lies entirely within the acceptance range on your drawing, it can ship straight away with no wait for custom production.

Values follow ISO 286-1; the table was cross-checked cell by cell against three independent sources on 2026-08-26 (6,674 cells agree, 0 errors). Coverage: shafts a–z and the corresponding uppercase holes, IT1–IT13, nominal sizes 0–500 mm. cd/ef/fg/za/zb/zc, sizes above 500 mm and grades above IT13 are not included: the tool reports "not found" and never extrapolates. Data sources and verification →

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