Joggers taper and cuff at the ankle. Sweatpants do not. That one difference decides almost everything else.
The two words get used interchangeably and they describe two genuinely different garments.
A jogger tapers from the thigh toward the ankle and finishes in an elasticated or ribbed cuff. The leg is closed at the bottom.
A sweatpant runs straight or wide from the thigh to a plain open hem. The leg is open at the bottom.
Both are usually made from the same fleece-backed knitted fabric and both usually have a drawstring waist. The ankle is the difference, and it changes more than it sounds like it should.
What the Cuff Changes
The silhouette. A jogger narrows the leg, which reads as neater and more athletic. A sweatpant keeps the volume all the way down, which reads as more relaxed and more current.
The shoe. A cuffed ankle sits above the shoe and shows the whole thing. An open hem falls over the shoe, so you need a shoe with enough presence to sit under it.
The warmth. A cuff seals the ankle, so joggers are warmer in cold weather. An open hem lets air move, which is more comfortable in a warm room.
The length tolerance. A jogger can be slightly too long and the cuff will absorb it. A sweatpant that is too long will drag on the floor, so the hem length matters more.
Which to Buy
It depends on what you want them to do.
Buy joggers if you want something neater, if you wear high-top sneakers or boots, if you want them to read as sportswear, or if you want the warmest option.
Buy sweatpants if you want the more current shape, if you prefer a wider leg generally, or if you want them to read closer to an ordinary trouser, which a wide straight sweatpant genuinely can in a dark color.
If you are buying one pair, a wide or straight sweatpant in black or charcoal is the more versatile, because a dark open-hem leg reads much closer to a trouser than a cuffed one ever will.
The Fit Details
The rise. A mid to high rise sits at the waist and is more comfortable. A low rise on a drawstring trouser will slide down as you move.
The drawstring. Should be long enough to tie properly and anchored so it cannot disappear into the waistband. A flat cord holds a knot better than a round one.
The waistband. A wide ribbed band sits flatter and holds better than a narrow one with elastic threaded through a channel.
The cuff, on joggers. Should be ribbed and springy. A loose cuff means the leg falls and the whole shape is lost, and it is the first thing to go.
The hem, on sweatpants. Should be level and finished. This is the pair to get hemmed if they are long, exactly as you would a trouser.
Pockets. Side pockets that lie flat rather than gaping. A zip pocket is useful and adds a hard line to a soft garment, which some people want and some do not.
The ankle is the whole difference, and it changes more than it sounds like it should.
Keeping Either One Looking Deliberate
Both read as loungewear by default. Four things change that.
Color. Black, charcoal and dark navy read closest to an ordinary trouser. Gray marl reads most obviously as a sweatpant. A bright color reads as sportswear.
An absence of branding. Logos, contrast stripes down the leg and large text all pull the garment toward gym clothing. A plain pair does not.
The top half. A plain knit, a crewneck or a collared shirt lifts them. A matching sweatshirt in the same fabric makes it a tracksuit, which is a deliberate look and an unmistakably casual one.
The shoe. A clean leather sneaker or a boot lifts them. A running shoe confirms them as gym clothing.
A plain black wide sweatpant with a fine knit and a clean leather sneaker is a genuinely presentable outfit. The same pair in gray with a logo and running shoes is not, and no styling changes that.
Where They Work and Where They Do Not
They work at home, traveling, running errands, the gym, a casual weekend, and in workplaces with genuinely no dress code.
They do not work anywhere with a smart casual expectation, because the visible elasticated waist is the first thing anyone reads and it sets the register regardless of what is above it. A black trouser is the piece that covers the same comfort at a higher register, and a drawstring trouser in a woven fabric splits the difference.
Wide-Leg Sweatpants
Worth a separate note, because they are the version of this garment that reads most current.
A wide-leg sweatpant is cut with volume all the way down and an open hem, more like a wide trouser than like gym clothing. With a high rise and a fitted top, the proportion is the same as a wide leg jean, and it works for the same reason.
The hem length matters more here than on any other version, because there is more fabric to pool. Get them hemmed if they touch the floor.
And the shoe needs presence, since a wide hem covers most of it. A chunkier sneaker or a boot rather than a thin low-profile shoe.
Caring for Them
Wash cold and inside out, which keeps the color and protects the brushed inside.
Tie the drawstring before washing so it does not pull into the channel.
Hang to dry or tumble on low. Heat shrinks the length and, on joggers, tightens the cuff.
Skip the fabric softener, which coats the fleece backing and makes it feel flat.
De-pill with a fabric shaver. The inner thigh goes first on any soft trouser and it is friction rather than wear. Browse the joggers edit for both shapes.
The Fabrics
French terry. Smooth on the outside, looped on the inside. Lighter than fleece and it breathes better, which makes it the more comfortable option indoors and in mild weather.
Brushed fleece. Smooth outside, soft brushed nap inside. Warmer, heavier, and the standard for winter. The nap flattens over time, which is what makes an old pair feel thin.
Washed or garment-dyed. Treated after construction so the color has depth and variation. Reads as more considered than a flat color and fades faster if washed warm.
A woven drawstring trouser. Not a sweatpant at all, but it belongs in the comparison. A woven fabric with a drawstring waist gives you the comfort with a trouser's appearance, and it is the option to look at if you want to wear something soft somewhere that would not accept a sweatpant.
Sizing
A drawstring waist hides a multitude of sizing problems, which is why people often buy these too large.
The waistband should sit without the drawstring doing all the work. If you need to pull the cord tight for them to stay up, the waist is too big and the rise will sag.
Check the thigh rather than the waist. A drawstring can be tightened and a thigh cannot be changed.
On joggers, check the cuff is not tight on your calf, which is the most common fit complaint and the one that makes a pair unwearable.
Joggers and Sweatpants
The Short Version
Joggers taper to a cuff and sweatpants have an open hem, and that single difference decides the silhouette, the shoe and the warmth. Buy a dark wide or straight sweatpant if you want one pair, since it reads closest to a trouser. Avoid logos and stripes, wear a proper knit and a clean shoe, and get an open hem shortened if it drags. Browse the joggers edit.