What do the numbers on piping tips mean refers to brand-specific size codes printed on each metal cone, not universal measurements. Wilton, Ateco, and generic makers each run their own scale within every shape family, which is why a Wilton 1M and an Ateco 824 can look nearly identical while a “size 10” from a vintage tin behaves like a modern “size 4.” The number only marks a tip’s place in that manufacturer’s lineup.
This guide covers how Wilton and Ateco assign their numbers, how to read letter suffixes, and which tip numbers pair with the most common decorating tasks. It targets home bakers who want to walk into a supply shop or browse online and know exactly which tip to add to the cart.
Why Piping Tip Numbers Exist in the First Place
Stamping a single digit on a metal band saves space and gives decorators a shorthand faster than reading words. A maker who produces 80 round tips cannot engrave “medium-large round, 9 mm opening” on every band, so the tip gets a code: 3, 4, 10, 12, and so on. The number has nothing to do with millimeters, fractions of an inch, or any cross-brand standard.
Each brand builds its own scale, then holds to it across every shape. A round 3 from Wilton and a round 3 from Ateco line up because both companies chose to start their round-tip line at a small opening and work upward. A star 16 from Wilton means something different internally than a star 16 from Ateco, because the star family counts ridges, not millimeters, and the two companies do not always match ridge counts at the same number.
Without the numbering system, every tip would need a label the length of a pencil. Numbers keep the catalog scannable and the drawer organized, but they only make sense once you know the brand and shape family behind them.
That catalog logic varies wildly by maker, which is why comparing Wilton, Ateco, and generics side by side reveals some sharp mismatches.
How Wilton, Ateco, and Generic Brands Number Their Tips
Wilton treats its numbers as a simple size ladder inside each shape category. Round 1 is the smallest round opening it sells, and round 12 is roughly six times wider. Star 16, star 18, and star 22 all sit in the same closed-star family, with the number climbing as the ridges get deeper and the opening wider. Open star tips follow the same logic, which is why 1M, 2M, and 3M march upward in size.
Ateco mirrors Wilton’s round and many star numbers on purpose, so Wilton 16 round and Ateco 16 round produce nearly identical lines for lettering and borders. Ateco’s specialty shapes, especially the drop flowers and French piping tips, carry their own numeric codes like 824, 827, and 869 that reference internal product IDs rather than size. Those numbers usually line up with a Wilton equivalent for common shapes, which is why so many decorators treat the two brands as interchangeable for everyday work.
The Cross-Brand Translation You Actually Need
| Shape | Wilton Number | Ateco Equivalent | Typical Use |
|---|---|---|---|
| Round, fine | 1, 2, 3 | 0, 1, 2 | Dots, eyes, small lettering |
| Round, medium | 4, 5, 6 | 3, 4, 5 | Writing, dots, fine detail |
| Round, large | 10, 12 | 8, 9, 10 | Cake writing, borders, drop flowers |
| Open star | 1M, 2M, 3M | 824, 826, 827 | Rosettes, cupcakes, swirls |
| Closed star | 16, 18, 21, 22 | 16, 18, 21, 22 | Shells, rope borders, grass |
| Petal | 104, 125 | 104, 125 | Ruffled flowers, bows |
| Leaf | 352 | 352 | Foliage, vines, accents |
Generic or unbranded sets usually borrow the Wilton or Ateco scale, but imported tins sometimes follow a European numbering system that only matches if you measure the opening yourself. French piping tips, including the Saint-Honoré nozzles and straight-sided cones used in patisserie, often skip the abstract number and stamp the opening size in millimeters directly on the metal. When you see “8 mm” stamped on a cone, the guesswork is gone.
Once the numeric gap between brands is clear, the cryptic letters and shape codes printed beside them start to carry real meaning.
Decoding the Letter Suffixes and Shape Codes
Letters on piping tips are shape and size tags, not abbreviations for flower names. Wilton uses them to mark specialty tips that do not fit a clean numeric ladder, while Ateco leans on its longer numeric codes to do the same job. Learning a handful of letters saves you from staring at a rack of metal cones wondering which one makes a ruffle and which one makes a leaf.
Wilton Letter Suffixes Worth Memorizing
- M suffix (1M, 2M, 3M): Marks a “medium” open star, the classic tip for cupcake swirls and rosettes.
- D suffix (1D, 2D, 3D): Flags the drop-flower tip, which cuts five petals in one squeeze.
- B suffix (2B, 3B): Identifies the basketweave tip, with a flat side that creates woven ribbon textures.
- C suffix (1C, 2C, 3C): Points to petal tips with a curved edge for soft ruffles and bows.
- Suffixless specialty tips: Numbers like 104 (petal), 125 (ruffled petal), and 352 (leaf) stand alone without letters because the shape is so distinct.
Ateco’s system leans on numeric codes that double as product IDs. Tip 824 is the company’s open star matching Wilton 1M, while 827 mirrors Wilton 2M. Tip 869 is the Ateco drop flower, roughly equal to Wilton 1D. The internal numbers look chaotic at first, but the pattern is consistent once you compare them to a Wilton chart.
Star tip point count is built into the shape itself, not the number, which catches a lot of decorators off guard. Two star tips labeled 16 from different brands can produce different textures if one has 8 points and the other has 10. The number only tells you size, never how many ridges you will feel in the icing.
Those shape codes translate directly into the textures and patterns most home bakers are actually trying to pipe.
Matching Specific Tip Numbers to Common Decorating Tasks
Picking a tip by task is faster than picking by number once you know the shapes, but the numbers anchor your shopping list so you do not leave the store with four stars and nothing to write with. Most home projects lean on a tight cluster of tips that handle 80 percent of the work without crowding your drawer.
Writing, Dots, and Fine Details
Round tips in the 1 to 5 range handle almost every fine line you will ever pipe. Round 3 and round 4 are the standard pair for lettering on cakes, dots on sugar cookies, and eyes on character figures. Round 1 is the smallest practical opening, useful for micro-details and royal icing lace. Round 5 gives you a slightly bolder line for names and short messages without looking chunky.
Rosettes, Swirls, and Cupcake Tops
Open star tips 1M, 2M, 18, and 21 produce the swirled cupcake top, buttercream rosette, and generous border that show up on most celebration cakes. Ateco equivalents like 824 and 826 do the same job with slightly different ridge depths. For a classic bakery-style swirl, the 1M is the most forgiving choice because it holds its shape with buttercream of almost any firmness.
Borders, Shells, and Textured Lines
Closed star tips in the 16 to 22 range transform plain buttercream into textured shells, rope borders, and tufts of grass across cake landscapes. Wilton 16 is a soft, beginner-friendly shell tip. Wilton 18 adds deeper ridges for borders that read clearly from across the room. Wilton 21 and 22 are the workhorses for grass, fur, and textured accents on novelty cakes.
Flowers, Petals, and Leaves
Petal tip 104 makes ruffled flowers and bow decorations, while leaf tip 352 covers most foliage needs on a single-tier cake. Wilton 125 and 126 produce more dramatic ruffles for full blooms. Drop-flower tips 1D, 2D, and 3D cut five-petal blossoms in a single squeeze, which is why they show up so often on vintage piping practice sheets.
Why Frosting Consistency Changes How a Tip Number Behaves
The number on a tip is only half the equation. A round 16 piped with stiff American buttercream behaves like a thick ribbon, while the same round 16 piped with thin royal icing flows like a thread and lays down a delicate line. The opening is identical. The frosting does the talking.
When the Tip Fights You
Star tips need a firmer consistency to hold their ridges. Soft buttercream collapses the points, and the result looks like a smooth ribbon rather than a star. If a tip number refuses to pipe, the problem is usually the icing, not the tip. Soften stiff frosting by a few seconds in the microwave with a tablespoon of milk, or drop one tip size down if the bag feels like a workout.
Room temperature matters as much as recipe. Cold buttercream clumps inside petal tips and tears the ruffle, so condition your bag and icing for 10 to 15 minutes before you start piping delicate shapes.
The Buttercream-to-Tip Cheat Sheet
- Stiff buttercream (peaks stand firm): Pair with open stars 1M and 2M, closed stars 18 through 22, and petal 104 for sharp definition.
- Medium buttercream (soft peaks): Works with round 3 to 12 for writing, open star 1M for swirls, and leaf 352 for soft foliage.
- Soft buttercream (barely holds a peak): Stick to round tips 2 to 8 for fine lines and let stars rest until the frosting firms up in the bowl.
- Royal icing (fluffy, flows easily): Use round 1 to 5 for lace and detail, round 10 to 12 for run-out borders and flat-flooding.
Measuring an Unlabeled or Vintage Tip and Building a Starter Kit
Loose metal cones often show up at estate sales, thrift shops, and the bottom of handed-down baking tins. Without a stamp, the only way to know what you are holding is to measure the opening across its widest point. A digital caliper reading in millimeters gives you the real size, and you can match that number against a brand chart in seconds.
How to Measure an Orphan Tip
Set the tip on a flat surface with the narrow end up. Place the caliper jaws across the opening at the widest point, including any teeth or serrations if it is a star tip. Round tips measure cleanly, petal tips need a measurement at the narrow end and the wide end, and star tips get measured tip-to-tip across the points. A 9 mm round opening roughly matches a Wilton 6, and a 13 mm opening matches a Wilton 10, though the exact mapping depends on the brand.
A Four-Tip Starter Kit
- Round 3: Handles dots, eyes, fine lettering, and royal icing detail.
- Round 12: Covers cake writing, medium borders, and drop-flower petals.
- Open star 1M: Produces the classic cupcake swirl, rosette, and generous border.
- Petal 104: Makes ruffled flowers and bows for one-tier celebration cakes.
Adding a closed star 18 and a leaf tip 352 later rounds out the kit for borders, flowers, and foliage on tiered cakes. Photograph any tip you buy next to a ruler, save it in a phone album, and you will never again wonder what that loose metal cone in your drawer actually does.
Bottom Line
Piping tip numbers are brand-specific size codes, not measurements, and the letter suffixes mark shape families more than size steps. Once you learn that Wilton 1M is the open star for swirls, Wilton 104 is the ruffled petal, and round 3 is the fine-lining workhorse, every tip in your drawer has a job. Measure the opening on any unmarked tip, pair the shape with the right frosting consistency, and the numbers stop being a mystery and start being a shortcut.
FAQ
Are piping tip numbers the same across brands?
Numbers are brand-specific and identify size within a shape family, not universal measurements. Wilton and Ateco share many round and closed-star codes, but open stars and specialty shapes often use different numbers for the same physical tip.
What does the M mean on Wilton tips like 1M and 2M?
The M suffix marks a “medium” open star tip, the classic shape for rosettes, cupcake swirls, and generous borders. 1M is smaller, 2M is medium, and 3M is the largest of the three.
How do I know what size a vintage or unmarked tip is?
Measure the opening across its widest point with a digital caliper in millimeters, then match that measurement against a brand chart. Round tips measure cleanly, while petal and leaf tips need both narrow-end and wide-end measurements.
Do larger tip numbers produce larger decorations?
Within a single shape family, higher numbers mean wider openings, taller ridges on stars, and broader petals. The decoration itself also gets taller as the tip grows, so a Wilton 22 star creates a noticeably taller shell than a Wilton 16.
Which tip numbers should a beginner buy first?
A four-tip starter set covers most home decorating: round 3 for fine detail, round 12 for writing and borders, open star 1M for swirls, and petal 104 for flowers. Add closed star 18 and leaf 352 when you start working on tiered cakes.
Does the same tip number behave differently with different frostings?
Yes. A round 16 piped with stiff American buttercream lays down a thick ribbon, while the same opening with thin royal icing flows like a thread. Match tip number to frosting stiffness for the cleanest results.
