Grade 5 vs Grade 23 Titanium Watches
Last updated
Grade 23 is the higher-purity sibling of Grade 5. Both are Ti-6Al-4V; Grade 23 is the ELI, or extra-low-interstitial, version. Here is what that means on a watch.
The short version
Chemically they are the same alloy. Grade 23 removes more of the trace interstitial elements, mainly oxygen and iron, which makes it slightly tougher, more ductile, and even more biocompatible, at a small cost in peak strength. On the wrist the two are practically indistinguishable in hardness, weight, and scratch resistance.
| Property | Grade 5 | Grade 23 |
|---|---|---|
| Full name | Ti-6Al-4V | Ti-6Al-4V ELI (extra low interstitials) |
| Purity | Standard interstitial levels | Lower oxygen and iron, higher purity |
| Toughness | High | Higher fracture toughness and ductility |
| Strength | Marginally higher peak strength | Slightly lower, more damage tolerant |
| Biocompatibility | Excellent | Medical-implant grade |
| On the wrist | Hard, scratch resistant, light | Effectively identical |
Same alloy, cleaner recipe
The ELI in Grade 23 stands for extra low interstitials. Reducing the dissolved oxygen and iron makes the metal tougher and more forgiving of stress, which is why Grade 23 is the choice for medical implants. The everyday hardness and light weight that define Grade 5 carry straight over.
How rare Grade 23 actually is
| In the catalog | Grade 5 | Grade 23 |
|---|---|---|
| References | 426 (27%) | 18 (1%) |
| Brands using it | 163 | 4 |
| Median price | $6,305 | $20,650 |
| Median case size | 41 mm | 41.05 mm |
| References with a published weight | 121 | 5 |
This is the part worth knowing before you spend time on the comparison. Grade 23 is 18 references from 4 brands in this guide, against 426 Grade 5 references from 163 brands. It is not a choice most buyers will ever face, and where it appears it is at the top of the market: a median of $20,650 against $6,305 for Grade 5.
So treat this page as a spec-sheet decoder rather than a buying decision. If a maker prints Grade 23 or ELI, you now know what it means. It is very unlikely to be the reason you pick one watch over another.
Why a brand chooses Grade 23
For a watch the appeal is purity and skin compatibility rather than a difference you can feel. Cartier, for instance, uses what it calls Grade 5 ELI, which corresponds to Grade 23. Treat a Grade 23 case as a slightly higher-purity Grade 5: excellent, and functionally the same on the wrist.
TudorPelagos FXD GMT
StraumJan Mayen Titanium
FormexAria Manufacture Chronometer (Titanium)
PaneraiLuminor Marina Titanio 44mm
OmegaSeamaster Planet Ocean Ultra Deep 6000M (Titanium)
IWCPilot's Watch Performance Chronograph 41 AMG (Titanium)
BlancpainFifty Fathoms Bathyscaphe Titanium
CartierSantos de Cartier Large (Titanium)
LaventureMarine Type 3
ApiarGen1.1 MR^2
BlancpainFifty Fathoms Automatique 42mm Titanium
BlancpainFifty Fathoms Tech Gombessa TitaniumFrequently asked questions
Is Grade 23 titanium better than Grade 5?
They are the same alloy. Grade 23 is the higher-purity ELI (extra low interstitials) version of Grade 5, marginally tougher and more biocompatible with slightly lower peak strength. For a watch the practical difference is negligible.
What is Ti-6Al-4V ELI?
ELI stands for extra low interstitials: the same Grade 5 alloy refined to contain less oxygen and iron, which improves toughness and biocompatibility. Cartier markets its version as Grade 5 ELI, which corresponds to Grade 23.