Candle Wick Types: A Working Chandler's Guide to Picking the Right One

The wick is the single biggest lever you have over how a candle behaves. Same wax, same fragrance, same jar. Swap the wick family and the candle is a different product. Most beginner problems I get sent (tunneling, mushrooming, sooting, weak hot throw) trace back to the wrong wick before they trace back to anything else.

Here is how I think about the four families, the sizing rules I actually use, and the two or three traps that catch people on their first 50 pours.

The four wick families

Almost every wick on the market belongs to one of these.

Flat braided cotton (LX, RRD, Premier). Three bundles of cotton braided flat so the tip curls slightly into the flame as it burns. The curl is self-trimming, which means less mushrooming and less soot. Good in soft waxes (soy, coconut blends). My default for 7 cm to 9 cm soy containers.

Square braided cotton (#1/0, #2/0). Tighter braid, holds shape better, runs a touch hotter. Best in harder waxes (beeswax, pillar paraffin) and in taper or pillar candles where you want a stable upright flame, not a curl.

Cored wicks (CD, ECO, HTP, CDN). Cotton (or cotton-paper) braid wrapped around a stiffening core. The core keeps the wick upright in deep melt pools so it doesn't drown. CD and ECO are the workhorses for container soy and coconut soy; HTP is a paper-cored hybrid that runs hotter and suits dense fragrance loads or wide vessels. CDN is a flat-braid variant of CD with a tighter curl, useful when CD is mushrooming.

Wooden wicks (single, booster, cross-ply). A flat strip of FSC-certified hardwood (usually cherry or birch). They crackle, throw a wider but shallower flame, and need a wider melt pool than cotton to throw well. Wonderful in coconut and coconut-soy blends; finicky in pure soy unless you boost them.

How to read a wick code

Wick codes are not standardised across manufacturers, but within a single series they are ordered. CD 8 is smaller than CD 10 is smaller than CD 12. ECO 4 is smaller than ECO 8. The number roughly tracks the wick's burn rate, not its diameter. Step up one size at a time when testing; jumping two sizes usually overshoots into mushrooming and soot.

Across manufacturers the codes do not translate. An ECO 10 and a CD 10 are not interchangeable, even in the same wax. Pick a series, learn its behaviour in your wax, and only switch series when you've ruled out everything else.

Matching wick to wax

This is the table I keep next to the pour station. Use it as a starting point, then test.

Pure soy (Golden 464, KeraSoy 4130): CD or ECO are the safe defaults. Flat braid (LX, RRD) for small vessels under 7 cm. Avoid wooden wicks unless you boost them.

Coconut soy blends (CoCoSoy, Cal-Wax C3): CD, HTP, or wooden wicks all work. Coconut blends release fragrance readily, so you can wick down half a size compared to pure soy in the same vessel.

Pure coconut wax: Wooden wicks come into their own here. Cotton CD also works but the wood gives the wax its best showcase.

Beeswax (container): Square braid or large CD. Beeswax is dense; undersized wicks drown immediately. Expect to be one size larger than you'd use in soy.

Paraffin (container): HTP or LX. Paraffin throws strongly and burns hot, so the cooler-running cotton wicks pair best.

The wick chart below cross-references these families to vessel diameter so you can pick three candidates to test rather than five.

Sizing rules I actually use

Wick by melt pool, not flame height. The candle is correctly wicked when the melt pool reaches the inside of the glass at the 2 to 3 hour mark on the first burn and stays at 5 mm to 10 mm depth (a fingernail's depth) on subsequent burns. Flame height is a secondary check.

If the pool reaches the glass at 90 minutes and the wax is too liquid (the wick visibly leans, the flame is over 3 cm tall), you're a size too big. Drop one.

If the pool hasn't reached the glass by hour 3 on a vessel under 8 cm wide, you're a size too small. Step up one.

Test with the candle fully cured (14 days for soy, 48 hours for paraffin). Testing a 24-hour-old soy will mislead you every time.

Mushrooming, sooting, drowning: what each one means

Mushrooming (a black carbon ball forming on the wick tip) means the wick is delivering more fuel than the flame can burn cleanly. Usually the wick is too big for the fragrance load, or the fragrance has a high vanillin content (vanillin chars). Drop one wick size; if mushrooming continues at a smaller size, switch series (CD to CDN, or ECO to LX).

Sooting (black smoke, soot on the inside of the jar) usually means the flame is being disturbed (drafty location) or the wick is untrimmed. Trim to 5 mm before every burn. If the candle soots in still air with a trimmed wick, you're a size too big.

Drowning (the wick sits in liquid wax and self-extinguishes) means the wick is too small or, in wooden wicks, the booster is missing. Step up one size or add a booster strip.

Wooden wicks: the specific notes

Wooden wicks need a 25 mm to 30 mm (1 inch to 1.2 inch) minimum vessel diameter to throw properly; below that they choke. They want a slightly higher fragrance load (8 to 10% in coconut soy) to crackle audibly. They need a flat trim with nail clippers, not scissors, before every burn (about 3 mm above the wax). And they hate drafts more than cotton wicks do, so place them away from open windows.

If your wooden wick won't stay lit past the first 10 minutes, it almost certainly needs a booster (a second thin strip glued behind the main wick). Most suppliers sell boosters separately and they fix 80% of wooden-wick complaints I see.

A 20-minute decision flow

1. What wax? Soy → CD or ECO. Coconut soy → CD, HTP, or wooden. Beeswax → square braid or large CD. Paraffin → HTP or LX.
2. What vessel diameter? Look up the size on the wick chart. Pick three candidates: one below the recommended size, one at it, one above.
3. Pour identical test candles with each wick. Cure fully. Burn 3 hours and judge by melt-pool reach plus depth, not flame height.
4. Pick the one that reaches the glass at hour 3 with a 5 mm to 10 mm pool depth. That's your wick for that wax-and-vessel combination. Don't change it when you change fragrance, unless the new fragrance has more than 5% vanillin.

Updated 25 June 2026. Fact-checked against BS EN 15493:2019.