Looking for some eye bolts (screw eye bolts) but can’t seem to get past all the complicated types and size variations?
We get it.
It’s tough looking at all these numbers and trying to decide which one will suit your needs best.
You could be using it to lift some items and secure a rope through it.
You might be wondering how much can it hold?
That’s where an eye bolt size chart can come in handy.
Searching for the right eye bolt is easier once you understand all the types, grades and dimensions.
The good news is that we’re here to help you navigate the numbers maze.
With a few in-depth explanations about each eye bolt specification and its types, you’ll be on your way to picking out the perfect ones for your project.
How to Read an Eye Bolt Size Chart
Before we get into it (or scroll down below to the screw eyes size chart if you just can’t wait!), we should note that not all size charts are created equal.
Some may include more details, such as eye bolt weight capacity, shoulder length, and diameter.
That being said, let’s focus on the main dimensions.
There are usually six components you can use to measure your bolt.
Each one has its own column.
They’re the eye bolt’s overall length, shank length, outside eye diameter, inside eye diameter, thread length, and shank diameter plus TPI (thread-per-inch).
Other specifications could be the forged code marking on the eyelet, which determines the material of the bolt.
Let’s take a deeper look into each one.
Shank, Thread, and Overall Length
This column will help you know all your eyebolt’s length measurements.
The overall length measures the eyebolt from top to bottom.
The Shank’s length determines the size from right below the eye to the end of the bolt.
Meanwhile, the thread length measures the intertwined area at the bottom.
Ultimately, your eyebolt length will decide how big the item is that you’re lifting.
This is important:
It can also be a great measure of how thick the piece you’ll be inserting the eyebolt in.
For instance, it could be bolted in a piece of wood or simply used for a children’s swing.
In which case, you’d want a lengthier eyebolt for each one.
Outside and Inside Screw Eye Diameter
The star of the show, or in this case, bolt, is the eye.
Its diameter will help you decide what you’ll be putting through it.
If you’re using eyebolts for lifting items using rope, then a larger diameter can be more accommodating.
We recommend measuring your cable or rope’s thickness first before deciding which eyebolt to get.
After all, you wouldn’t want to get an eye bolt only to realize that your inside and outside eye diameter is too small.
Shank Diameter and TPI
This might be one of the most important eye bolt specifications in this chart.
This measurement looks at the eye bolt’s shank thickness and thread-per-inch.
If you’re planning on doing some heavy-duty lifting, you might want to opt for a thicker shank diameter to support the weight, such as a ?-9.
This dimension can hold up to 7,000 lbs.
Looking for a lighter option?
We recommend checking for a ¼-20, which can hold a more reasonable 500 lbs.
TIP: Check out our full chart below to find all sizes, dimensions and weight limits for eye bolts.
Types of Screw Eyes Bolts
After taking a look at eye bolt sizes, you might want to decide which type of eye bolt to consider for your project.
Luckily, all size measurements are the same for all the types of eye bolts out there making things much easier.
The two main eye shapes you might find are drop-forged and formed eye bolts.
The latter will prove more useful if you’re finishing up a small DIY project, while the former is better suited for heavier loading.
Without further ado, here are a few types of the most commonly used eye bolts.
Lag Eye Bolts
Just like with lag screws these types of eye bolts are more commonly used in wood.
Lag eye bolts have a special feature, where you don’t necessarily need to measure their weight capacity.
Instead, you can focus on what you’re bolting it into. The harder the wood material, the sturdier and more secure your lag eye bolt will hold.
Collar Eye Bolts
As their name suggests, these threaded eyelets are collared between the eye and shank.
They’re especially well-suited for wire tensioning and carrying heavy loads.
It gets better.
You can use collar eye bolts for axial loading.
The collar essentially helps in providing extra hold for the thread when inserted in your working space.
One thing’s for sure, it won’t bend on you.
Apart from its shank strength, you should note that the inside eye diameter is smaller than most other types of eye bolts.
Shoulder Eye Bolts
If you’re looking to lift an item at a slight angle, then you might want to use a shoulder eye bolt.
While it can provide adequate support, you should always proceed with caution when holding anything at an angle.
The weight capacity of the eye bolt decreases as your holding angle increases.
You should also keep the angle to the side of the eye, rather than perpendicular to it.
Marine Eye Bolts
Planning on leaving these eye bolts out for a while?
Then, you might want to consider these corrosion-resistant threaded eyelets.
Their stainless-steel material might ensure you a longer lifespan, compared to other eye bolts.
The drop-forged eye bolt could also provide you with ideal strength.
Eye Bolt Size Chart
Check out this comprehensive screw eyes bolt size chart:
|
Shank |
Fraction (inches) |
Decimal (inches) |
Weight Capacity (lbs) |
|
1/2 |
0.5 |
2,500 |
|
|
1/4 |
0.25 |
600 |
|
|
1 |
1 |
10,000 |
|
|
2 |
2 |
35,000 |
|
|
7/8 |
0.875 |
7,200 |
|
|
3/8 |
0.375 |
1,300 |
|
|
3/4 |
0.75 |
5,200 |
|
|
5/16 |
0.3125 |
900 |
|
|
Inner Eye |
Fraction (inches) |
Decimal (inches) |
Weight Capacity (lbs) |
|
1 |
1 |
2,500 |
|
|
1/2 |
0.5 |
600 |
|
|
2 |
2 |
10,000 |
|
|
3-1/4 |
3.25 |
35,000 |
|
|
1-3/4 |
1.75 |
7,200 |
|
|
3/4 |
0.75 |
1,300 |
|
|
1-1/2 |
1.5 |
5,200 |
|
|
5/8 |
0.625 |
900 |
|
|
Outer Eye |
Fraction (inches) |
Decimal (inches) |
Weight Capacity (lbs) |
|
2 |
2 |
2,500 |
|
|
1 |
1 |
600 |
|
|
4 |
4 |
10,000 |
|
|
6-7/8 |
6.875 |
35,000 |
|
|
3-1/2 |
3.5 |
7,200 |
|
|
1-1/2 |
1.5 |
1,300 |
|
|
2-13/16 |
2.813 |
5,200 |
|
|
1-1/4 |
1/25 |
900 |
|
|
Overall |
Fraction (inches) |
Decimal (inches) |
Weight Capacity (lbs) |
|
4-3/16 |
4.188 |
2,500 |
|
|
3-7/32 |
3.219 |
600 |
|
|
9-5/8 |
9.625 |
10,000 |
|
|
19 |
19 |
35,000 |
|
|
8-1/4 |
8.25 |
7,200 |
|
|
4-1/4 |
4.25 |
1,300 |
|
|
6-7/8 |
6.875 |
5,200 |
|
|
3-23/32 |
3.719 |
900 |
|
|
Shank |
Fraction (inches) |
Decimal (inches) |
Weight Capacity (lbs) |
|
2 |
2 |
2,500 |
|
|
2 |
2 |
600 |
|
|
6 |
6 |
10,000 |
|
|
12 |
12 |
35,000 |
|
|
5 |
5 |
7,200 |
|
|
2-1/2 |
2.5 |
1,300 |
|
|
4 |
4 |
5,200 |
|
|
2-1/4 |
2.25 |
900 |
|
|
Thread |
Fraction (inches) |
Decimal (inches) |
Weight Capacity (lbs) |
|
1-5/8 |
1.625 |
2,500 |
|
|
1-1/2 |
1.5 |
600 |
|
|
3 |
3 |
10,000 |
|
|
4 |
4 |
35,000 |
|
|
3 |
3 |
7,200 |
|
|
1-1/2 |
1.5 |
1,300 |
|
|
3 |
3 |
5,200 |
|
|
1-1/2 |
1.5 |
900 |
FAQs
What are the uses of an eye bolt?
You can use them to lift, push, or pull any items, for swings, wire tensioning, rigging, anchoring, etc.
How are eye bolts measured?
Eye bolts are measured from below the eye.
What are the strongest eye bolts to use?
The drop-forged eye bolts are stronger and more reliable than the formed types.
An Example of Using an Eye Bolt Size Chart
The best way to get the hang of understanding a chart is by using it in an example.
Let’s assume you’re bolting a tire swing for a kid’s play area (I actually did this!).
After going through the size chart, I was able to easily pick out the perfect eye bolts.
The first thing you want to do is find out how much the tire weighs and any and all riders’ weights!
You can then decide how many holding points you want to install (i.e., how many eye bolts you’ll use).
In this case, let’s say you use two eye bolts to evenly distribute the weight capacity and surface area.
Since this would require an angled lift, you can opt for a shoulder eye bolt to better support the weight.
Now it’s time to decide the size dimensions.
From the weight capacity you can find out the exact size you’re looking for. I recommend looking at an eye bolt load rating chart.
Let’s say you want to hold 500 to 600 lbs because you want this to be robust enough to hold two adults (should that ever happen!).
You can then pick out a ¼-20 eye bolt, which is a standard eye bolt size.
The length of the eye bolt doesn’t necessarily need to be too long.
After all, you’re simply screwing it through a tire.
You can use washers if you want to fill up space in between the eye and shoulder of your eye bolt.
Afterward, you might want to measure your rope’s thickness to get a clue about your eyelet’s outside in inside diameter.
That’s it! You should now be able to pick out your eye bolt based on the measurements in the size chart.
—–
An eye bolt size chart will help you figure out which bolt to use based on the weight capacity.
Before inserting any eye bolts on your working surface, decide whether it’ll be at an angle or not.
The chart will pinpoint the detailed lengths and diameters in your eye bolt.
Apart from measurements, the type of bolt will also play a crucial role in terms of quality and material.
We hope you found this eye bolt size chart helpful for your next project.
John
Thursday 14th of September 2023
Can an eye bolt be installed through wood at a 45° angle in order to decrease the angle from the chain suspending it? Thanks!
Woody
Friday 10th of February 2023
Outstanding explanation. Well done.