Buying a replacement guitar bridge is not just about choosing the right style or finish. The most important part is making sure the new bridge actually fits your guitar.
Many players buy the wrong bridge because they do not check the bridge type, mounting style, or key dimensions before ordering. The result may be a bridge that does not line up with the existing holes, does not sit correctly on the body, or places the strings in the wrong position.
This guide explains the key measurements you should check before buying a replacement guitar bridge, what those measurements mean, and how to measure them as accurately as possible.
Guitar Bridge Measurement Terms Every Player Should Know
Before measuring your guitar, first identify the bridge type and mounting style. Different bridge designs may share some measurements, but they often use different mounting methods and require different key dimensions to ensure proper fit.
Bridge Type / Mounting Style
Start by confirming what type of bridge your guitar uses. Common types include Tune-O-Matic, wraparound, 6-point tremolo, 2-point tremolo, and hardtail bridges.
Even if two bridges look similar, they may not share the same post spacing, screw layout, bushing size, or body cavity requirements. This should be the first thing you check before comparing product specifications.
Post Spacing / Stud Spacing
Post spacing, also called stud spacing, is the distance between the centers of the two posts that hold a bridge in place.
This measurement is especially important for Tune-O-Matic bridges, wraparound bridges. If the post spacing does not match your guitar, the bridge will not mount correctly.
Always measure from the center of one post to the center of the other post, as shown below.
Post Diameter
Post diameter refers to the width of the bridge posts or studs.
If you are keeping your existing posts and only replacing the bridge itself, make sure the replacement bridge fits your current posts. If you are replacing the full mounting hardware, confirm that the new posts and bushings match the holes already drilled in the guitar body.
Bushing Diameter and Insert Depth
For bridges that use body inserts or bushings, such as many Tune-O-Matic and wraparound bridges, you may also need to check the bushing diameter and insert depth.
The bushing diameter should match the size of the existing hole in the guitar body. The insert depth should match the depth of the drilled cavity, so the bushing can sit properly without being forced into the body.
This matters most when replacing the full mounting set, not just the bridge itself.
Screw Spacing
Screw spacing refers to the distance between mounting screws.
For a 6-point tremolo bridge, measure from the center of the outermost screw hole on one side to the center of the outermost screw hole on the other side. This helps confirm whether the full screw layout matches the replacement bridge.
If the screw spacing is different, the new bridge may require drilling new holes.
Pivot Post Spacing
Pivot post spacing refers to the distance between the centers of the two pivot posts used on 2-point tremolo bridges and some double-locking tremolo systems.
You can also check the distance between the centers of the two knife-edge notches on the bridge plate, since these are the points that sit against the pivot posts. If the pivot post spacing does not match your guitar, the bridge may not sit on the posts correctly or move smoothly during tremolo use.
Bridge Plate Length and Width
Bridge plate length and width refer to the overall size of the bridge base plate.
This matters most for tremolo bridges and hardtail bridges. If the bridge plate is too large, it may not sit correctly on the guitar body or may interfere with an existing route. If it is too small, it may leave old screw holes or unfinished areas exposed.
Tremolo Block Size
For tremolo bridges, the tremolo block is the metal block that extends below the bridge plate into the guitar body cavity.
Check the block length, width, and depth to make sure it fits inside the tremolo cavity. If the block is too deep or too large, it may hit the body cavity and affect tremolo movement.
String Spacing
String spacing is the distance between the centers of the outermost strings, usually measured from the low E string to the high E string at the bridge.
This measurement affects how the strings sit over the fretboard and pickups. For most bridge replacements, string spacing should be measured at the saddles, not at the nut.
Tools You Need to Measure a Guitar Bridge
The right tools can help you get more reliable measurements and avoid buying a bridge that does not fit.
For most bridge measurements, a digital caliper is the best option. A standard non-digital caliper can also work if you know how to read it correctly. If neither is available, use a ruler only for rough reference.
You will need:
- A digital caliper, or a standard caliper if available
- A notepad or phone to record measurements
- Good lighting
- Your current bridge still installed, if possible
Most guitar hardware specifications are listed in millimeters, so it is best to measure in millimeters first. You can convert to inches later if needed.
Keep in mind that measurement errors can still happen. The caliper may be slightly angled, the center point may be hard to locate, or the part itself may have small manufacturing variations. Measure key dimensions more than once and compare your results with the product specifications before ordering.
If the difference is very small, it may fall within normal measurement or manufacturing tolerance. But if the difference is obvious, especially around key mounting points such as post spacing, screw spacing, or pivot post spacing, it is safer to choose another bridge.
What to Measure for Different Guitar Bridge Types
Different bridge types require different key measurements. Use the table below as a quick checklist before comparing your guitar with a replacement bridge product page.
You can also browse different guitar bridge types and compare their specifications before measuring your own guitar.
|
Bridge Type |
Key Measurements to Check |
|
Tune-O-Matic Bridge |
Post spacing, post diameter, bushing diameter and insert depth, bridge width, string spacing |
|
Wraparound Bridge |
Post spacing, post diameter, bushing diameter and insert depth, overall bridge length, string spacing |
|
Vintage 6-Screw Tremolo Bridge |
Screw spacing, bridge plate length and width, string spacing, tremolo block size |
|
2-Point Tremolo Bridge |
Pivot post spacing / knife-edge notches , post diameter, bridge plate size, string spacing, tremolo block size |
|
Hardtail Bridge |
String spacing, bridge plate length and width, mounting screw spacing, string-through or top-loading layout |
This table does not mean every bridge replacement requires every measurement. It is a quick reference to help you focus on the measurements that matter most for your bridge type.
If these terms still feel abstract, the examples below will make them easier to understand. We’ll use a Tune-O-Matic bridge and a 6-point tremolo bridge to show how the main measurements are taken with a caliper.
Example 1: How to Measure a Tune-O-Matic Bridge
Below is an example using the Guyker GM008 Tune-O-Matic bridge. The image shows the main measurements you may need to compare, including bridge size, post spacing, string spacing, post diameter, and bushing dimensions.
Use the image as a visual reference when checking your current bridge against a replacement product page. Compare the same measurements on both parts instead of relying on appearance alone.
Example 2: How to Measure a 6-Point Tremolo Bridge
Below is an example using the Guyker GG1013A 6-point tremolo bridge. The image shows common measurements for this bridge type, including bridge plate size, tremolo block size, screw spacing, and string spacing.
For tremolo bridges, also make sure the tremolo block can fit inside the guitar body cavity. A bridge may look similar from the top, but the block size and screw layout still need to match.
Common Measuring Mistakes to Avoid
Measuring From the Edge Instead of the Center
Post spacing, screw spacing, and pivot post spacing should usually be measured from center to center. Measuring from the outside edge of one post or screw to the outside edge of another can give you the wrong number.
Measuring String Spacing at the Nut
For bridge replacement, string spacing should usually be measured at the bridge saddles, not at the nut. Nut spacing and bridge spacing are different measurements.
Assuming All Similar Guitars Use the Same Bridge
Do not assume that every LP-style, SG-style, Strat-style, or Tele-style guitar uses the same bridge measurements. Different brands, factories, and production years may use different hardware dimensions.
Final Thoughts
A replacement bridge should be chosen by measurements, not appearance alone. Before ordering, compare your guitar’s key dimensions with the product specification sheet and measurement images carefully.
Guyker bridge product pages include detailed specifications and measurement images, so you can compare the key dimensions more easily before choosing a replacement.
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