Locksport Tools

Interactive tools for understanding lock mechanisms and security systems.

Educational Purposes Only

These tools are for educational purposes and understanding lock mechanisms. Only use on locks you own or have permission to test.

Locksport Resources

Universal Bitting Decoder

Decode key bitting codes for various lock manufacturers.

Use Tool

Master Lock Decoder

Interactive calculator to find Master Lock combinations (see below).

Use Calculator

Elevator Key Chart

Reference chart for common elevator key types and codes.

View Chart

Bitting Depth Tables

Look up bitting depths and spacing for common lock manufacturers.

View Tables

Master Lock Decoder

Find the combination to a Master Lock using physical measurements. Original concept and algorithm by Samy Kamkar. Watch the video tutorial.

Inputs

First Locked Position (between non-integers)1

Second Locked Position (between non-integers)2

Snag Number3

1Find the "First Locked Position"

Set the dial to 0
Pull on the shackle and rotate counter-clockwise (towards 10) until the dial clicks into a gap
If you're between two integers (e.g., 3 and 4), reset and continue to test the next gap
If the dial crosses an integer (e.g., between 3.5 and 4.5), enter the number in-between (e.g., 3)

2Find the "Second Locked Position"

Reset and continue turning counter-clockwise until you find a gap below 11 that crosses a second integer
Enter this number (e.g., if between 5.5 and 6.5, enter 6)
If you only find ONE locked position under 11, try between 10-20, then subtract 10

3Find the "Snag Number"

Lightly pull the shackle so you can turn the dial
Rotate clockwise until you feel resistance at only one point
Verify the dial snags at the same place several times
If the snag begins at a half number (e.g., 14.5), enter 14.5

4Find & Narrow Results

Click "Find Combinations" to get possible combinations
Test the third digit options by pulling the shackle and noting rotation
Select the number with the larger gap to narrow to 8 combinations
Test all 8 until one works! Click tested combos to track progress

Video Tutorial

Watch Samy Kamkar's original demonstration of the Master Lock decoding technique:

Master-Key Privilege Escalation Planner

Starting point: 6 chambers on the horizontal axis, with depth rows sourced from the selected lookup table (including #0 where available). Enter the change-key bitting to auto-mark excluded depths using table-derived master-pin rules.

Instructions

Select cylinder type and manufacturer, then enter change-key depths at positions 1-6 using valid cut numbers for that system.
The grid marks that exact depth as Change.
Excluded depths are table-driven: any depth difference not represented by supported master-pin delta multiples is auto-marked Invalid.
Assumption: one master pin per stack. Once a master depth is identified for a position, all other remaining candidates in that column are marked Discarded.
All remaining cells in that column are shown as Test.
Example: if position 1 is depth #2 and the table supports deltas {2,4}, then #4 and #6 are Test while #1, #3, and #5 are Invalid.

Cylinder Type

Manufacturer

Assumptions

1-bit master-pin support is auto-detected from the selected table's master pin values

Detected adjacent depth step(s): 0.0150, 0.0150, 0.0150, 0.0150, 0.0150, 0.0150, 0.0150, 0.0150, 0.0150 • Master pin increment(s): 0.0300

Why: No master pin size or increment matches 0.0150. Supported depth deltas from master pins: ±2, ±4, ±6, ±8.

6-Position Bitting Grid

Table source: Schlage • Depth rows: #0, #1, #2, #3, #4, #5, #6, #7, #8, #9

Depth	Position 1	Position 2	Position 3	Position 4	Position 5	Position 6
Change Key
#0
#1
#2
#3
#4
#5
#6
#7
#8
#9
Master Bitting (Minimum)	—	—	—	—	—	—
Master Bitting (Deep)	—	—	—	—	—	—
Master Pins	—	—	—	—	—	—

Exclusion rule active (table-driven): one-bit support is not detected, and unsupported depth deltas are excluded for each measured position.

Click Test/Blocked/Shear chips to toggle test result per depth. Strategy rows use Change and Shear depths per chamber: Minimum = min(Change, Shear), Deep = max(Change, Shear).

Once each chamber has enough test outcomes to determine a master pin depth, the table lists all valid master bitting combinations for below/above/same shear placement.

Bitting Analysis & Reference Tables

Analyze key bitting depths, validate cuts, check MACS violations, and reference technical specifications. All measurements in thousandths of an inch.

Cylinder Type

Lock System

Shift (Optional)

Shift: Negative values = deeper cuts

Root Depths (Leave unused positions blank)

Enter up to 7 root depths in thousandths of an inch (e.g., 200, 214, 259). Leave empty to use Schlage example.

Key Specifications

Set	Shoulder/Tip to First	Center to Center	MACS	Step Size
Default	.231"	.156"	7	0.0150

Bitting Depth Table

Cut #	Root Depth	Bottom Pins	Master Pins
0	.335	.165	—
1	.320	.180	—
2	.305	.195	.030
3	.290	.210	—
4	.275	.225	.060
5	.260	.240	—
6	.245	.255	.090
7	.230	.270	—
8	.215	.285	.120
9	.200	.300	—

MACS (Maximum Adjacent Cut Specification) indicates the maximum difference allowed between adjacent cuts. A dash (—) indicates that data is not available or not applicable for that specification.