Estimate crown molding in linear feet, sticks, cost and cut angles
This crown molding calculator turns each room's ceiling line into the linear feet of crown you actually have to buy — then into whole stock lengths ("sticks"), a material cost, and the exact compound miter and bevel to set on your saw. Enter a room's length and width (or a direct ceiling perimeter for an irregular room), set the stock length, waste and price, and read the takeoff. Crown runs the full ceiling, so nothing is subtracted for doors.
It handles a whole house at once: add every room and the totals roll up across rooms before rounding, the way molding is really bought in bulk. The cut-angle card is the part a plain trim calculator skips — give it your spring angle and it returns the compound miter and bevel for a flat-on-the-saw cut, plus cope-inside / miter-outside guidance. Everything runs in your browser; nothing you type is sent anywhere.
What crown molding is, and how it is measured
Crown molding is the trim that bridges the top of the wall and the ceiling, sprung out at an angle rather than lying flat against either surface. Because it follows the ceiling line, its run is simply the room's perimeter — a doorway never interrupts the ceiling, so unlike baseboard, crown is never shortened for openings.
For a rectangular room that means the crown run is twice the length plus the width. In the plan below, the crown ring runs unbroken all the way around the room, with a marker at each corner. The calculator counts crown on this full ceiling perimeter, from either the room's dimensions or a perimeter you type directly.
Crown runs the full ceiling
Crown (full ceiling line)Inside corner — copeOutside corner — miter
A 12 × 14 ft room: the crown ring runs unbroken around the whole ceiling, with a marker at each corner — nothing is subtracted for doors.
The measuring formula
Crown reduces to a short chain: the ceiling perimeter, a waste allowance, a round-up to whole sticks, and a cost — plus the compound-angle formula that turns your spring angle into saw settings. The room perimeters are summed across the whole project before the waste and round-up are applied, so buying rolls up the way it does at the supplier.
Every room reduces to these steps, summed across the project before rounding — plus the compound-angle formula that turns your spring angle into saw settings.
Crown run — the ceiling line
crownLF = 2 × (Length + Width)- Doors are never subtracted — crown runs the full, unbroken ceiling.
- In perimeter mode, enter the ceiling perimeter directly instead of L × W.
Stock lengths to buy
sticks = ceil( crownLF × (1 + waste%) ÷ stock length )- Room runs are summed first, then rounded once at the project level.
- Waste defaults to 15% for crown and is editable.
Material cost
cost = sticks × stock length × price/ft (or sticks × price/stick)- Cost is figured on whole sticks — the crown you actually carry home.
- Enter a per-foot or per-stick price; both resolve to the same spend.
Compound miter and bevel
tan(M) = sin(θ) × tan(corner ÷ 2); sin(B) = cos(θ) × cos(corner ÷ 2)- θ is the spring angle; corner defaults to 90° for a square room.
- M is the miter (table) angle, B the bevel (blade tilt), for a flat cut.
Inside and outside corners: cope vs. miter
A plain rectangular room has exactly four inside (concave) corners and no outside corners — a geometric fact, so in dimensions mode the calculator fills those counts in for you. Outside (convex) corners only appear when the room is not a simple rectangle: an L-shape, a chimney chase, or a soffit return. Enter those in perimeter mode, where both counts are editable.
Inside corners are usually coped — the first piece runs into the corner square, and the second is scribed to its profile so the joint stays tight even when the walls are not a true 90°. Outside corners are mitered — two angled cuts meeting at the point. Corner counts are informational here: they shape the diagram and tell you where to cope and where to miter, but the extra material those cuts consume is folded into the waste percentage rather than added as a separate quantity.
Inside vs. outside corners
Crown (full ceiling line)Inside corner — copeOutside corner — miter
Corner markers distinguish coped inside corners from mitered outside corners — here a perimeter-mode run with three inside and one outside corner.
Spring angle and the compound miter and bevel
Crown is sprung, so cutting it is not a single 45° miter — it is a compound cut with both a miter angle (the table swing) and a bevel angle (the blade tilt). Which pair you set depends on the molding's spring angle: the angle between the back of the crown and the wall when it is installed. The two dominant profiles are 38° (the common US "52/38" crown) and 45° (a symmetric "45/45").
The calculator computes the compound angles from the spring angle and the corner angle rather than reading them off a chart, so it also handles a custom spring angle or an out-of-square corner. For a square 90° corner the standard values are below; the cross-section figure shows the same numbers on the molding itself. These settings assume the crown is cut lying flat on the saw table (nested against the fence is a different method).
| Spring angle θ | Miter (M) | Bevel (B) | Where you see it |
|---|---|---|---|
| 38° | 31.6° | 33.9° | The common US "52/38" crown — the default in this calculator. |
| 45° | 35.3° | 30.0° | A symmetric "45/45" profile, common on taller and European crown. |
Spring-angle cross-section
The 38° spring angle measured off the wall, with the resulting compound miter (31.6°) and bevel (33.9°) shown on the molding profile.
Stock lengths and waste, and why we round to whole sticks
Crown is sold in fixed lengths, not by the foot: MDF and softwood crown is most commonly stocked in 12 ft lengths, with 16 ft available and longer pieces usually needing special freight. You buy whole sticks and cut them on site, so the honest number is the count of sticks — which is why the calculator rounds the waste-adjusted linear feet up to the next whole stick and prices what you actually carry to the till.
Waste covers the compound-miter and coped offcuts, test cuts to dial in the angle, and the odd mistake. Crown earns a higher default than flat trim — 15% — because its compound cuts and coped returns burn more material than a straight 45°. Bump it up for stain-grade material, where grain and color matching waste more, or for a room with many corners; drop it for a simple paint-grade rectangle.
Using the calculator, step by step
The tool is built around a room list and a single crown profile. Work through it in order:
From rooms to a shopping list and saw settings
- Choose your units and currencyPick metric or imperial and your currency. Imperial (feet) is the default for the US-centric crown market; switching converts your entries and leaves the cut angles unchanged.
- Add your roomsAdd a room for each space. Enter length × width for a rectangle, or switch to perimeter mode and type the ceiling perimeter directly for an L-shaped or bay room, along with its inside and outside corner counts.
- Set the crown materialConfirm the stock stick length (12 ft is the crown default), tune the waste percentage, and add a price per foot or per stick to cost the job.
- Set the cut anglesPick the spring angle — 38°, 45° or a custom value — and, for an out-of-square room, the corner angle. The rail returns the compound miter and bevel plus cope-and-miter guidance.
- Read the takeoffThe rail shows crown linear feet, whole sticks, cost and the saw settings. Export the per-room takeoff to CSV or print it for the supplier and the shop.
Worked examples
Two quick takeoffs — a single room's crown from its dimensions, then the compound-angle math for a 38° spring — show exactly how the linear feet, sticks, cost and saw settings fit together.
Two worked examples, using the calculator's default 12 ft crown sticks, 15% waste and 38° spring angle.
One room's crown from its dimensions
crown — full perimeter- Given
- Living room, 12 × 14 ft
- Doors and openings are ignored — crown runs the full ceiling
- Crown: 12 ft sticks, 15% waste, $6.00/ft
- Formula
sticks = ceil( crownLF × 1.15 ÷ 12 )- Steps
- Ceiling perimeter = 2 × (12 + 14) = 52 ft
- With waste: 52 × 1.15 = 59.8 ft
- Sticks: 59.8 ÷ 12 = 4.98 → round up to 5
- Cost: 5 sticks × 12 ft × $6.00 = $360
- Result
- 5 sticks of crown — about $360, on the full 52 ft ceiling
Compound miter and bevel for a 38° spring
cut angles — square corner- Given
- Spring angle θ = 38° (a 52/38 crown)
- Square corner: 90°, so corner ÷ 2 = 45°
- Crown cut lying flat on the saw table
- Formula
tan(M) = sin(38°) × tan(45°); sin(B) = cos(38°) × cos(45°)- Steps
- tan(M) = 0.6157 × 1 = 0.6157 → M = 31.6°
- sin(B) = 0.7880 × 0.7071 = 0.5572 → B = 33.9°
- Set the miter to 31.6° and the bevel (blade tilt) to 33.9°
- Cope inside corners; miter outside corners
- Result
- Miter 31.6° · bevel 33.9° — the standard 38° crown settings
Perimeter mode: the unrolled ceiling line
Crown (full ceiling line)Inside corner — copeOutside corner — miter
When a room is entered as a direct perimeter, the plan can't be drawn, so the crown run is shown unrolled as a straight band with evenly spaced corner ticks.
Common mistakes to avoid
Subtracting doorways from crown (it runs the full ceiling, so it is never shortened), rounding each room to whole sticks separately instead of summing first, setting a plain 45° miter instead of the compound miter and bevel for the spring angle, and pricing raw linear feet instead of the whole sticks you actually buy — these are the four errors that throw a crown estimate or a cut off. This calculator avoids all four by design.
Frequently asked questions
The details that come up most often when estimating and cutting crown.
How much waste should I add for crown molding?
15% is a sensible default for crown, higher than the 10% used for flat trim because its compound miters and coped returns waste more material and often need a test cut or two to dial in. Add roughly 5 more points for stain-grade material, where you are also matching grain and color, or for a room with lots of corners; drop it a little for a simple paint-grade rectangle. One thing the percentage only approximates: any wall longer than a single stock length needs a scarf splice, and the offcut that splice leaves is folded into the waste allowance rather than counted exactly — so a run of long walls may take an extra stick beyond what the takeoff shows. The calculator seeds 15% and lets you edit it.
What is the spring angle, and how do I find mine?
The spring angle is the angle between the back of the crown and the wall when it is installed — most crown is either 38° or 45°, and the value is often printed on the molding or its packaging. If it isn't, sit an offcut into a square corner between two scraps and measure the angle it makes with the wall. The spring angle, not the corner, sets the compound miter and bevel, so getting it right is what makes the joint close.
Should I cope or miter crown corners?
Cope inside (concave) corners and miter outside (convex) corners. A coped inside joint — the first piece square into the corner, the second scribed to its profile — stays tight even when the walls are not a true 90°, which they rarely are. Outside corners have to be mitered, two compound cuts meeting at the point. The calculator's cut card gives the miter and bevel for the mitered cuts and reminds you which corners to cope.
What stock lengths does crown come in?
MDF and softwood crown is most widely stocked in 12 ft lengths, with 16 ft available; longer pieces often need special freight, which is why 12 ft is the DIY default and the calculator's starting value. Hardwood and plaster crown vary more by supplier. The stock length is editable, so if your supplier quoted 16 ft you can just type it and the stick count updates.
Should I price crown per foot or per stick?
Both are supported. Retailers usually quote a per-linear-foot price for comparison, so that's the default, but the physical product is a fixed-length stick with a shelf price. Whichever you enter, the cost is always figured on the whole sticks you actually buy, so per-foot and per-stick pricing stay consistent with each other.
Related calculators
Crown is usually one of the last jobs in a room. These neighboring estimators cover the surfaces and trim around it.