
Know your Gap?
Know your blade gap
If you shave with a double-edged or single-edged safety razor, you may know about blade gaps and their relationship to how aggressively a razor shaves. But most of you do not know the actual gap of your razor (or razors). There is no good reason to know how wide of a gap there is between your razor blade and the razor’s safety bar if you are happy with your shave. How wide of a gap between the blade and the razor is just one factor contributing to aggressiveness. The best measure is how your razor feels to you.
However, I can think of two good reasons to know your blade gap. The first is if you are a beginner and your current razor isn’t giving you as good a shave as you hoped for, the gap is a starting place to discover a razor that works better for you. Perhaps you feel as if your razor isn’t doing anything because it takes more than three passes to get your beard taken down to smooth skin. You need a more aggressive razor. The opposite situation is if you really hoped to like wet shaving with a safety razor, but no matter what you do, your skin is irritated, and you end up with nicks and cuts. Try a less aggressive razor.
You need to know where your razor is to know where to go next, and the razor gap is one easy measure to help you identify the razors you want.
The second reason is one that pertains mostly to me. I am a retired scientist. I am curious. Measuring things and analyzing the data is, for me, fun.
I measured the gap on the three razors I own. A Merkur 34C measured 0.020 inches. My Leaf Twig single-edged razor (which uses half of a double-edged blade) measured 0.019 inches. Finally, the Vikings Blade Chieftain JR measured 0.024 inches. The measurements correspond to my impression of the feel of each razor. The 34C and the Twig feel very similar and mild. The Chieftain JR felt more aggressive but not too much so.

I am not the only one who has measured the blade gaps of razors. You can find the information online at several sources. Unfortunately, not every razor has been measured. Also, some of the numbers do not agree with others. This could be an experimental error in the measurements, poor measurement technique, or a real difference because of the age of the razor, even a difference between batches due to minor design changes. However, most of these differences are small and wouldn’t impact any decision you made regarding a comparison between razors.
The Merkur 34C is on all the lists because it is popular. My measurement agrees with what others reported, which gives me confidence that the measurements I made for the Twig and the Chieftain JR are accurate.

If you switch to an adjustable razor, knowing how your non-adjustable razor’s gap compares to the gap at the different settings on the adjustable will suggest where to start, although, again, just shaving until you find a setting that feels right is the best guide to adjusting your razor.
Gap measurements of Safety Razors
Blade Gap Size inches | Razor & Setting |
---|---|
0.008 | Rockwell Razor R1 |
0.010 | Above the Tie M1 & M2 |
0.011 | Standard Fatboy Setting 1 |
0.012 | Rex Ambassador Setting 1 |
0.014 | Rockwell Razor R2, Aristocrat Slim Setting 1 |
0.015 | Merkur Progress Setting 1, Standard Fatboy Setting 2, Standard Slim Setting 1 |
0.016 | Aristocrat Slim Setting 2 |
0.017 | Standard Fatboy Setting 3, Standard Slim Setting 2 |
0.018 | Muhle R89 |
0.019 | Rockwell Razor R3, Timor, Standard Fatboy Setting 4, Leaf Twig |
0.020 | Merkur 34C, Executive Shaving Co. Mild Outlaw, Aristocrat Slim Setting 3 |
0.022 | Merkur 20C, Merkur Progress Setting 2, Standard Slim Setting 3 |
0.023 | Above the Tie R1 & R2 |
0.024 | Above the Tie S1 & S2, Rockwell Razor R4, Vikings Blade Chieftain JR |
0.025 | Gillette Flare Tip, Rex Ambassador Setting 3, Rex Envoy, Aristocrat Slim Setting 4, Standard Fatboy Setting 5, Standard Slim Setting 4 |
0.026 | Aristocrat Slim Setting 5 |
0.027 | Rockwell Razor R5, Standard Slim Setting 5 |
0.028 | Merkur Progress Setting 3, Executive Shaving Co. Braveheart |
0.028 | Executive Shaving Co. Outlaw |
0.029 | Muhle Rocca |
0.030 | Standard Fatboy Setting 6, Standard Slim Setting 6 |
0.031 | Rockwell Razor R6, Aristocrat Slim Setting 6 |
0.033 | Merkur Progress Setting 4, Aristocrat Slim Setting 7, Standard Fatboy Setting 7 |
0.034 | Standard Slim Setting 7 |
0.035 | Aristocrat Slim Setting 8, Standard Fatboy Setting 8 |
0.036 | Above the Tie H1 & H2, Standard Slim Setting 8 |
0.037 | Merkur Progress Setting 5, Standard Fatboy Setting 9 |
0.039 | Aristocrat Slim Setting 9, Standard Slim Setting 9 |
0.051 | Rex Ambassador Setting 6 |
Measurements for the above table are combined from the first two sources below, plus the measurements I made.
- Double Edge Razor Blade Gap Explained
- Adjustable Razor Blade Gaps – Gillette Adjustable Razors
- Double-Edged Safety Razors Ranked by Blade Gap | Badger & Blade
The table at Badger & Blade has gaps that do not agree with the other two sources. I don’t know which numbers are correct if either. The first two references are close but do not agree with each other for all the measurements.

