A jar wider than about 3.5 inches usually needs more than one wick. A single wick can only melt wax so far from the flame, so in a wide vessel one wick leaves a ring of solid wax around the edge while the center tunnels down. Adding a second or third wick spreads the heat across the surface so the whole pool reaches the glass. This guide covers the four decisions behind a multi-wick candle: when to add wicks, how many to use, how to size each one, and where to place them. For the full wick-sizing reference and our size chart, see the guide to wicking; to browse what we stock, visit our candle wicks collection.

When to Use More Than One Wick

Most wick types top out at a melt pool around 3 to 3.5 inches across. A few burn wider, up to about 5 inches, but relying on a single wick for that much coverage can create a flame that runs hot. Carbon collects on the wick tip before the pool ever reaches the edges, and you get soot and smoking that can coat the glass and dull the scent throw. Wick diameter controls how much soot a flame produces, and an overworked wick burns dirtier^[3].

So once a vessel passes about 3.5 inches in diameter, reach for a second wick rather than a single larger one. Two smaller flames cover the surface more evenly than one straining flame, melt the pool out to the glass, and burn cleaner.

How Many Wicks Your Candle Needs

A practical starting point is to add one wick for every inch of diameter past 3 inches. The table below applies that rule. It is a guideline, not a hard limit: you can run three wicks in a 4-inch jar if you prefer, as long as the wicks are sized down to match. Keep round jars to no more than three wicks at 4 inches, though, since a fourth flame that close to center crowds the jar and builds up too much heat.

Wicks by Jar Diameter (Starting Point)

Jar diameter	Wicks to start with	Notes
Up to 3.5 in	1	A single correctly sized wick
4 in	2	Up to 3 if sized down; avoid crowding
5 in	3	4 also works, especially in square jars
6 in	4	Space evenly to keep flames apart

Treat the count as a place to begin, then let a test burn confirm it. If the pool reaches the glass cleanly without the flames running tall or sooting, the count is right.

Sizing Each Wick

Once you know the diameter and the wick count, a simple equation gives the melt pool each wick needs to cover. Divide, then add a quarter inch of overlap so the pools meet in the middle instead of leaving a cold seam.

Size Each Wick With the Equation

1
Measure the jar diameter

Measure across the inside of the vessel at the wax surface, in inches. Use the inside width, not the outside of the glass.
2
Divide by the number of wicks

Take the diameter and divide it by how many wicks you plan to use. For a 4.5-inch jar with three wicks, that is 4.5 divided by 3, which is 1.5.
3
Add 0.25 inches of overlap

Add a quarter inch so neighboring melt pools overlap rather than leaving unmelted wax between them. 1.5 plus 0.25 gives 1.75.
4
Match the figure to a wick

Each wick should burn a melt pool up to about 1.75 inches across. Look that figure up on a wick sizing chart, then pick the wick rated for it.

The equation gives you a target melt-pool width; matching that width to a specific wick series is what the guide to wicking and its size chart are for. Each wick family behaves differently from one wax to the next, so use the chart to translate the 1.75-inch target into an actual wick, then confirm it with a test burn.

Where to Place the Wicks

Space the wicks evenly so their melt pools overlap and reach the glass, without clustering them so tightly in the center that the heat concentrates. The diagrams below show our recommended layouts. They are starting points; you can adjust the arrangement to suit a vessel, then test it.

Round Jars

In a round jar, set two wicks on a centered line, three in a triangle, and four in a square. Keep a 4-inch round jar to two or three wicks; step up to four once the jar reaches 5 inches.

Diagram labeled 4 Inch Diameter Round with a star in each half marking two wick positions — Two wicks in a 4-inch round jar, set on a centered line.

Diagram titled 4 Inch Diameter Round, circle split into thirds with a star wick in each — Three wicks in a 4-inch round jar, set in a triangle.

Diagram titled 5 Inch Diameter Round, circle quartered with a star wick in each quadrant — Four wicks in a 5-inch round jar, set in a square. Three wicks also work in this size.

Square Jars

Square jars are trickier because the corners sit farther from any flame, so one or two wicks can leave unmelted wax in the far corners. One or two wicks suit a small square jar; for a larger one, such as a 22-ounce cube, four evenly spaced wicks melt the corners best. The four-wick layout below shows a 5-inch jar but works well at 4 inches too.

Diagram titled 4 Inch Diameter Square, square split into two halves with a star wick in each — Two wicks in a 4-inch square jar, set parallel.

Diagram titled 4 Inch Diameter Square, divided diagonally with a star wick in each triangle — Two wicks in a 4-inch square jar, set diagonally to reach two corners.

Diagram titled 5 Inch Diameter Square, split into four squares with a star wick in each — Four wicks in a square jar, one per quadrant, to melt the corners.

Test Before You Commit

Wick selection is one of the hardest parts of candle making, and multiple wicks add a variable, so a test burn is the only way to confirm a layout works. Burn a sample candle and watch how the pools meet: they should reach the glass within a few hours without the flames running tall, sooting, or overheating the jar. If a corner stays solid or a flame towers, adjust the count, size, or spacing and test again. Our notes on Wick Testing walk through what to look for.

Getting a multi-wick candle right takes a few tries, so set the count and size from the rules above, then let the test burn settle the final layout. If you want a second opinion on a tricky vessel, our team is glad to help.

Sources

Candle Fire Safety U.S. Fire Administration (FEMA) ↩
Safety with candles National Fire Protection Association, 2024 ↩
Candle flame soot sizing by planar time-resolved laser-induced incandescence Scientific Reports (Nature), 2020 ↩

Frequently Asked Questions

What is a double wick candle?

A candle that uses two wicks to light a melt pool one wick cannot reach on its own. Wider vessels need the extra flame to melt the wax out to the glass, so makers add a second wick once a jar passes about 3.5 inches across. The same idea extends to three or four wicks in larger jars.

When should a candle have more than one wick?

Once the vessel is wider than about 3.5 inches. Most wick types burn a melt pool up to roughly 3 to 3.5 inches, so a wider jar leaves a ring of unmelted wax at the edge unless you add another wick. Below that diameter a single correctly sized wick is usually enough.

How many wicks should I put in a candle?

A practical starting rule is one wick for every inch of diameter past 3 inches: two wicks for a 4-inch jar, three for a 5-inch jar, four for a 6-inch jar. Keep round jars to no more than three wicks at 4 inches to avoid crowding, and always confirm the count with a test burn.

How do I figure out what size wick to use for multiple wicks?

Divide the jar diameter by the number of wicks, then add 0.25 inches. A 4.5-inch jar with three wicks gives 4.5 divided by 3, plus 0.25, which is 1.75, so each wick should burn a melt pool up to about 1.75 inches across. Use that figure with a wick sizing chart, then test.

Where do I place wicks in a candle jar?

Space them evenly so their melt pools overlap and reach the glass without crowding the center. In round jars use a centered line for two wicks, a triangle for three, and a square for four. In square jars set wicks parallel or diagonally for two, and in the four quadrants for four.