An evening dress is finished at the floor. Before anyone looks at the neckline or the fabric, the eye runs down to see where the hem ends and what is under it. That is why the heel is not a last-minute accessory: it sets how high the dress hangs, how long the line from hem to floor looks, and how the whole outfit walks into a room.
Three heel shapes cover almost every evening look: the stiletto, the kitten heel and the block heel. Each does a different job, and the choice matters most when the dress is long.
A stiletto is a thin, tall heel, usually 8 cm or more. It gives the longest visual line and the sharpest silhouette, and it suits fitted, formal dresses and anything cut to the floor. The trade-off is balance: all the weight sits on a tiny point, so it is the shape that asks for the most practice.
A kitten heel is a thin heel kept low, roughly 3 to 5 cm. It keeps the pointed, dressy look but is easier to walk in for a long evening. It pairs well with midi lengths and with slim trousers, where a tall heel can look like too much.
A block heel is thick and straight-sided, usually somewhere between 5 and 8 cm. The wide base spreads the weight, so it is the steadiest of the three. It reads as relaxed and modern, and it works with fuller skirts and wide-leg evening trousers.
A long dress is hemmed for one specific pair of shoes. Change the heel by even 3 cm and the hem moves with it: too high and the ankle shows when you wanted a clean floor-length line, too low and the fabric drags under your foot, which is the main reason people trip on stairs at events. The tool below lets you see this. Pick a heel shape, set the heel height, and say what heel height the dress was hemmed for.
Start with the hem, not the shoe. If the dress is already hemmed, try it on in the heel you plan to wear before the day, and walk up and down stairs in it. If the hem is wrong by more than two or three centimetres, a tailor can usually adjust it in a short appointment, and it is cheaper than buying a second pair of shoes.
Then match the heel to the dress. Slim, floor-length column dresses suit a stiletto or a slender kitten heel, because a thick heel can look heavy at the bottom of a clean vertical line. Fuller skirts, pleats and wide-leg evening trousers suit a block heel, which gives the volume above it something to stand on. A midi dress looks best in a kitten heel or a low block, since a very tall heel makes the gap between hem and shoe feel stretched.
Hem and heel are a pair. Change one and you have changed the other.
Colour does the rest. A shoe in the same shade as the dress, or in a skin-neutral tone, extends the line; a contrasting shoe in black or metallic draws the eye down on purpose. Neither is wrong, but pick one on purpose. Satin, patent and metallic finishes catch light and read as dressier, while matte suede is quieter.
An evening look only works if you can stand in it for hours. Padded insoles, a strap across the ankle or the instep, and a heel with a wider tip all help a shoe stay put. If the event involves standing on grass or cobbles, a block heel is the practical choice. Carry a pair of flat folding shoes if you want to dance.