To open a dial combination lock, turn the dial right three full turns and stop on the first number, turn left one full turn past the first number and stop on the second, then turn right to the third and pull the shackle. Number locks and locker locks work a little differently; here’s each one, from the makers’ own sheets.
Key takeaways
- On a dial padlock the pattern is right, left, right. Master Lock starts with three full turns to the right to clear the dial.
- On the turn to the left you go once all the way round, past the first number, before stopping on the second. That’s the step most people get wrong.
- Built-in school and gym locker locks use the same pattern, but you open them with the handle or the dial, not a shackle.
- Number (wheel) locks have no order at all: line every number up on the mark, then pull the shackle, push it down or press the release button, depending on the model.
- If a lock won’t open, start again from the beginning. Master Lock says that almost every “broken” lock it hears about is a forgotten combination.
In This Article
How to open a combination lock: the short answer
Everything on this page assumes you know the combination. With the numbers in hand, the only question is which kind of lock you’re holding, because each one takes the numbers in a different way. Right and left mean clockwise and anticlockwise as you look at the dial.
| Lock type | How you know it | Steps in one line |
|---|---|---|
| Dial padlock | A round dial numbered all the way round, a mark at the top, a loose padlock with a shackle | Right three turns to the 1st number, left one full turn past it to the 2nd, right to the 3rd, pull the shackle1 |
| Built-in locker lock | The same kind of dial, but fixed into the locker door | Right two or more turns to the 1st, left one full turn to the 2nd, right to the 3rd, then lift the handle or pull the dial2 |
| Number (wheel) lock | Three, four or five thumbwheels side by side | Line up every number on the mark, then pull the shackle, push it down or press the button, as your model needs345 |
Can’t remember the numbers at all? That’s a different problem, and we’ve given it its own page: what to do if you forgot your padlock combination.
How to open a dial padlock, step by step
This is the classic school and gym padlock: a round body, a black dial marked every five numbers from 0 to 35, and a small indicator at the top of the dial. The combination is three numbers, printed on a sticker on the back of a new lock or handed out by your school, and you enter them in the order on the tag.6 These steps are Master Lock’s, for its No. 1500D.1
- Clear the dial. Turn the dial to the right (clockwise) three full turns, and keep going until the first number lines up with the indicator. Stop there.
- Set the second number. Turn the dial to the left (anticlockwise). Go one full turn, past the first number, and stop when the second number reaches the indicator.
- Set the third number. Turn the dial to the right and stop on the third number. Don’t go round again.
- Open it. Pull up on the shackle, or hold the shackle and pull the lock body down.
Master Lock’s slide tutorial for the same lock adds two details. Step 2 is “ONE full turn to the left, passing the first number”, and if your lock has the larger silver body rather than the black-dialled one, you turn the dial to the left until it stops after step 3, before pulling the shackle.6 To lock it again, push the shackle back in. Master Lock’s own patent design locks the shackle by itself as it enters the case.7
Want to try it before you face a real lock with a queue behind you? The practice dial below runs the same three moves on screen.
Practise on a dial padlock
A made-up combination, just for practice
Your practice combination
Type your own numbers (0 to 39) or .
- Turn right (clockwise) at least three full turns, then stop on .
- Turn left, go past once, and stop on it the second time.
- Turn right straight to and stop.
- Pull the shackle.
Drag the dial round, scroll on it, or use the buttons. Start by turning right.
Common mistakes
- Skipping the clearing turns. The three turns right aren’t a ritual: they reset the dial, so the lock forgets whatever was dialled before.
- Stopping on the second number too soon. Going left, the first time the second number comes round doesn’t count. Go past the first number once, then stop.
- Overshooting. If you go past a number, don’t turn back to it. Start again from step 1 (the section on how the dial works explains why).
- Turning the wrong way first. Every Master Lock dial sheet we read starts to the right. If your lock came with its own instructions, they win.
- Going round again on the last number. The third number is a straight turn to the right with no extra pass.
Built-in locker locks (school and gym lockers)
Many school, college and gym lockers have the lock built into the door instead of hanging on a hasp. The dial looks the same, and so does the right, left, right pattern, but there are two differences: fewer clearing turns, and nothing to pull at the end except the locker itself. Master Lock prints one sheet for its built-in range, with a column for each family of models.2
- Turn the dial right two or more whole turns and stop at the first number.
- Turn left one whole turn past that number and stop at the second number.
- Turn right to the third number. What you do next depends on the model (below).
| Master Lock models | After the third number | Locking again |
|---|---|---|
| 1630, 1631 | Stop at the third number and lift the locker door handle | Relocks by itself when the door is closed |
| 1652 to 1655, 1657 | Keep turning right until the dial stops, then hold the dial and pull on it, or on the handle | Relocks by itself when the door is closed |
| 1670, 1671 | Keep turning right until the dial stops; the door then opens and closes freely | Close the door and turn the dial one full turn to the left |
If you don’t know which model you have, try the 1630 ending first: stop on the third number and lift the handle. If the handle won’t move, keep turning right until the dial stops.
One thing worth knowing about lockers you don’t own: the combination isn’t yours to lose. Master Lock’s sheet tells administrators to keep a chart of every lock’s serial number and combination, with the locker number and the name of the user, and to guard the chart and the control key used to change combinations.2 If you’ve forgotten a school locker combination, the office should have it on its chart.
Number locks: 3, 4 and 5-wheel padlocks
Wheel locks are the easy ones. There’s no direction and no order: the lock opens when every wheel shows the right number on the line at the same time. What varies is the last move. We read three makers’ sheets and found three different ones, which explains a lot of puzzled tugging in changing rooms.
- Turn each wheel until its number sits on the indicator line or stripe. Master Lock calls it the black indicator line on its ProSeries locks; Squire uses a red line.35
- Check that each number is in the middle of the line, not half a click either side.
- Open it the way your model works: pull the shackle up (Master Lock ProSeries, M175 and M178), push the shackle down into the body (Master Lock 175EURD), or press the release button under the body (Squire CP40, CP50 and CP60).345
- To lock, close the shackle and scramble the wheels.
A new lock comes set to a factory code, usually all zeros: 0-0-0-0 on four-wheel Master Lock and Squire models, 0-0-0 on three-wheel ones such as Master Lock’s 4680EURD.345 Set your own before you use it. Squire recommends doing that, and getting used to the lock, before you fit it to whatever you’re securing.5 On Master Lock’s Set-Your-Own models the code can only be changed with the lock open and set to its current combination, the same rule you’ll find on four-wheel key safes.8
Luggage locks and TSA locks
A combination luggage lock is a small wheel lock, and you open it the same way: line up the numbers, then press the button or pull the shackle. A “TSA lock” is one that airport security can also open without your numbers. Travel Sentry, which runs the scheme, says its accepted locks carry a red diamond logo and can be opened by authorised officers using special master keys, so a bag can be inspected without damaging the lock.9 The master key only matters to them. For you, it’s a number lock like any other.
The lock won’t open with the right combination
Master Lock’s own answer to “my lock is broken” is blunt: “99% of the time the lock is working perfectly, but consumers have forgotten their combination.”10 Before you blame the lock, work through this list.
- Start again from the clearing turns. A dial lock can’t be corrected halfway through. Three full turns right, then the sequence, slowly.
- Check the number order. The numbers go in the order on the tag or sticker, first to third.6
- Try the extra turn. On Master Lock’s larger silver-bodied dial padlock, the dial has to go left until it stops after the third number.6 On built-in locker locks, keep turning right after the third number until the dial stops.2
- Pull the right way. Pull the shackle up, or hold it and pull the body down.6 On a number lock, check whether yours wants a pull, a push or a button.
- Centre the wheels. On a number lock, a wheel sitting slightly off the line can stop it opening. Squire’s sheet shows the difference between numbers centred on the line and numbers that aren’t.5
- Don’t force it. Squire’s sheet has a plain warning: “do not pull on the lock”.5
- Stiff, sticky or frozen. Master Lock recommends a lock lubricant for locks that freeze in winter or stick from time to time. For hard-to-turn wheels, it suggests WD40 to clean the moisture out, followed by a proper lubricant.108
If none of that works and you’re sure of the numbers, the lock may be faulty. Master Lock Europe says its padlocks are warranted against mechanical defects for the life of the product and asks owners who think a lock is defective to contact it; Master Lock’s built-in locker locks carry a five-year guarantee.102
Every combination lock starts with three turns to the right.
Master Lock’s dial padlocks do. Its built-in locker locks ask for two or more whole turns.
A lock that won’t open is usually broken.
Master Lock says 99% of these locks are working and the combination has been forgotten.
On a number lock the wheels have to be set in order.
Order doesn’t matter. Every wheel just has to be on the line when you open it.
UK padlocks: Squire and Master Lock Europe
Most of the dial-padlock instructions online are American, but the method doesn’t change at the border. Master Lock Europe’s support pages give the same four steps for the 1500D as the US sheet, almost word for word: three times right to the first number, left past the first number to the second, right to the third, pull up on the shackle.10
Squire, the Wolverhampton firm, publishes a picture sheet for its CP40, CP50 and CP60 combination padlocks made from 2018 on. The CP40 and CP50 have four wheels and the CP60 has five.5 To open one:
- Turn the wheels to your code, centred on the red line (0000 on a new lock).
- Press the release button on the underside of the body.
- Lift the shackle out.
- To lock, push the shackle down and turn the wheels to hide your code.5
The same sheet covers recoding, which needs a screwdriver and the lock open. We tried to get Abus’s own instruction sheets for its combination padlocks too, but couldn’t open them, so we haven’t copied a retailer’s version onto the maker’s name. The leaflet in the packet is the safest guide.
Why the dial works this way
The right, left, right routine looks like superstition until you see inside. Master Lock’s own patent for a “permutation padlock”, filed by Harry E. Soref and James Keith Marshall in 1937 and granted in January 1938, shows three notched tumblers behind the dial. A driving disc is fixed to the knob, and each tumbler carries a small transfer lug, so one can carry the next round. The knob is “turned alternately in opposite directions to successive predetermined positions” until the notches line up. Only then can the tongue of the locking lever enter the notches, so the lever can tilt and free the shackle as you pull it.7
That’s why the first number takes the most turns. The full turns at the start gather up every tumbler, so all of them move together and the last one parks on your first number. Reverse, and you leave it there while you pick up the next; reverse again for the last. Sargent & Greenleaf’s guide to its safe locks describes the same chain of wheels picking each other up, on a bigger and heavier scale.11 Overshoot a number and you’ve dragged a tumbler past its spot, which is why the only fix is to start again.
“The shackle is automatically locked upon its entry into the lock case.”
Soref and Marshall, US patent 2,105,337 (1938)
The idea is far older than the school locker. In 1843 Linus Yale and Charles Wilson patented a combination safety-lock for doors that held its bolt until notches in pairs of disks lined up.12 By 1888 lock makers were working on changing the numbers easily: Thomas S. Spivey of Cincinnati patented, for the Victor Safe and Lock Company, a permutation lock with a combination changer.13
The big dial on an old safe door is the same machine with heavier wheels and more turns. Our guide to old safe combination locks explains how they’re dialled, and our history of lock mechanisms in safes follows the story from lever locks to time locks.
Frequently asked questions
Which way do you turn a combination lock first?
To the right (clockwise). Master Lock’s dial padlocks and its built-in locker locks both start with full turns to the right, then go left for the second number and right for the third.
Do you go past the second number or the first?
Master Lock’s sheets say to turn left one full turn past the first number and stop on the second. Some school handouts say “pass the second number once”. It’s the same movement: going left from the first number, you pass the second number once on the way round, then stop on it the next time.
Why do you have to turn the dial so many times at the start?
The opening turns clear the dial and pick up all the tumblers inside, so they move together. Each later change of direction leaves one tumbler behind on its number.
Can I change the combination?
Only on a resettable lock, and only while it’s open and set to the current combination. On Master Lock’s Set-Your-Own wheel locks, that’s done with the reset tool or by turning and pressing the shackle, depending on the model. Locker combinations are changed by the administrator with a control key.
What if I’ve forgotten the combination?
For a school locker, ask the office. For your own padlock, see our separate guide to forgotten padlock combinations.
Sources:
- Master Lock, “Master Lock Model #1500D: How to Use the Combination” (one-page sheet, hosted by The Home Depot): turn the dial 3 times to the right and stop on the first number; turn left, pass the first number and stop on the second; turn right and stop on the third; pull up on the shackle. Accessed 5 November 2026. ↩︎
- Master Lock Company, “Suggestions for administering your Master Lock built-in combination locks” and “Combination dialing instructions for built-in locker lock products”, sheet 7000-0074 (Milwaukee, 2003), models 1630/1631, 1652 to 1657 and 1670/1671. Accessed 5 November 2026. ↩︎
- Master Lock, “ProSeries resettable combination padlock instructions” (1177D sheet; copy hosted by a retailer): first opening at 0-0-0-0; dials set at the black indicator line; “The dials of a lock with a valid combination do not rotate when the shackle is open”; to reopen, dial the combination and pull the shackle. Accessed 5 November 2026. ↩︎
- Master Lock Europe, “Set-Your-Own combination locks: instructions and FAQs”: 175EURD “DIAL your secret number and DEPRESS shackle”; M175EURDLF and M178EURD “DIAL your combination and PULL shackle”; factory settings of 0-0-0-0 or 0-0-0 depending on the model. Accessed 5 November 2026. ↩︎
- Henry Squire & Sons, “CP40, CP50 & CP60 (2018+): how to set your own code” (illustrated instruction sheet, Wolverhampton): factory code 0000 lined up on the red line; release button under the body; CP40 and CP50 four wheels, CP60 five; numbers centred on the line; “do not pull on the lock”; Squire recommends setting your own code before fitting the lock. Accessed 5 November 2026. ↩︎
- Master Lock, “How to use a Master Lock combination lock: step-by-step instructions” (7-slide tutorial for the standard dial padlock body; copy hosted by the retailer Rothco): combination on the back of the lock or handed out by the school; three turns right to the first number; one full turn left passing the first number to the second; right to the third; larger silver-bodied locks need a turn left until the dial stops; pull up on the shackle or pull the lock down. Accessed 5 November 2026. ↩︎
- US Patent 2,105,337, Harry E. Soref and James Keith Marshall, “Permutation padlock”, filed 4 February 1937, granted 11 January 1938 (original assignee Master Lock Co.), via Google Patents. ↩︎
- Master Lock, 178D FAQ sheet (copy hosted by a retailer): resetting Set-Your-Own models 175, 176, 177 and 178 with the reset tool, only with the lock open and set to the current combination; lubricant for locks that stick from time to time. Accessed 5 November 2026. ↩︎
- Travel Sentry, “TSA lock”: “A TSA Lock is a luggage lock that can be opened by authorised security officers using special master keys”; accepted locks carry the Red Diamond logo; used by security agencies in 80+ countries. Accessed 5 November 2026. ↩︎
- Master Lock Europe, “Padlocks: service and support FAQs”: 1500D opening steps; “99% of the time the lock is working perfectly, but consumers have forgotten their combination”; lock lubricant for frozen locks; WD40 to clean hard-to-turn wheels followed by a good lubricant; padlocks warranted free from mechanical defects for the life of the product. Accessed 5 November 2026. ↩︎
- Sargent & Greenleaf, Mechanical Safe Lock Guide (© 2006): operating instructions, “Combination Lock Glossary” and “Troubleshooting/Dialing Diagnostics”, pp. 2–12, PDF, archived copy. ↩︎
- US Patent 3,312, Linus Yale and Charles Wilson, “Combination safety-lock for doors”, 20 October 1843, via Google Patents. ↩︎
- US Patent 390,528, Thomas S. Spivey, Cincinnati, assignor to the Victor Safe and Lock Company, 2 October 1888 (filed 14 January 1888), via Google Patents. ↩︎
