What is the difference between gochugaru and paprika?

Gochugaru vs Paprika

The short answer

Both are ground or flaked red chilli with more colour than heat, and they are not substitutes. Gochugaru is a coarse Korean flake, sun-dried, fruity and moderately hot, and its texture is part of what it does — it sits visibly in kimchi and stews rather than dissolving. Paprika is a fine powder, usually from sweeter cultivars, and Hungarian and Spanish grades differ from each other more than either resembles gochugaru. Using paprika in kimchi gives colour without the fruit or the heat, and the texture is wrong.

Side by side

Gochugaru and Paprika compared side by side
	Gochugaru	Paprika
Botanical identity	Capsicum annuum L.	Capsicum annuum L.
Part used	fruit	fruit
Origin	Capsicum annuum originates in the Americas. Chilli reached Korea in roughly the late sixteenth or early seventeenth century, and the Korean cultivars and the sun-drying practice developed there afterwards.	The Americas; Capsicum was domesticated in Mesoamerica and South America and carried to Europe after 1492.
Flavour notes	fruity, sweet, smoky, warm	sweet, fruity, red-pepper, smoky (smoked grades), mildly bitter
Heat	1500–10000 SHU (typically 4000 SHU)	0–1000 SHU (typically 250 SHU)
Flavour	Fruity, mildly sweet and gently smoky, with a warm rounded heat that builds slowly and never spikes. The absence of bitterness is as distinctive as the heat: with the seeds gone there is nothing sharp in it, which is what allows it to be used in the quantities kimchi demands.	Sweet and gently fruity with a mild bitterness, and a body that gives dishes depth without heat. The smoked grades are assertively smoky and reduce everything else on the plate to a supporting role if used heavily.
Aroma	Fruity and faintly sweet, with a sun-dried, almost raisin-like quality in good Korean product and very little of the acrid note of hotter chillies.	Sweet, fruity and faintly tomato-like in the unsmoked grades; oak-smoked pimentón adds a pronounced, persistent smokiness that dominates the aroma.

Can you swap them?

Substitution is directional: the answer is often different in each direction, and both are recorded.

Paprika with Cayenne pepper

Acceptable

Use: ~1× by volume — Equal total volume, roughly six parts sweet paprika to one part cayenne. Adjust the cayenne by taste; the paprika is doing the colour and the bulk.

A far better answer than crushed flakes, and an unintuitive one. Paprika supplies the colour, the mildness and the fruity sweetness — it is the same species processed a different way — and a little cayenne restores the heat. What is missing is the texture: paprika is milled smooth where gochugaru is coarse and slightly damp, so kimchi made this way looks uniformly red rather than flecked.

How the replacement compares on each sensory axis
Flavour	Aroma	Colour	Heat
partial	partial	close	similar

Works for

Stews, soups and sauces where the chilli is dispersed anyway
Marinades and dressings
Getting the colour right when that matters more than the texture

Does not work for

Kimchi, where the visible flecks are part of what it should look like
Anything wanting the sun-dried, faintly raisin-like aroma of good Korean product
Dishes where smoked paprika is all that is available — the smoke is wrong here

Cuisine: Gets closer to Korean than crushed flakes do, but a Korean cook will see it. Gochugaru is bought by origin and drying method in Korea, which is not the behaviour of an interchangeable ingredient.

Established culinary practice

Use sweet paprika, not smoked. Smoked paprika brings a note that does not belong in Korean food and it will be the first thing anyone tastes.

Which should you buy?

Gochugaru

Gochugaru is only sold milled, so the usual whole-versus-ground advice does not apply — the choice is grind and origin instead. Buy coarse if you make kimchi and fine if you mostly make stews and sauces; buy Korean sun-dried once to know what it tastes like, then decide honestly whether you can tell in the dish you actually cook. Buy small quantities however good it is, because it fades within months, and put it in the freezer when you get it home.

Paprika

Ground is the only form, so the decision that matters is which paprika. Treat sweet, hot and smoked paprika as three separate ingredients in the cupboard rather than variants of one, because substituting between them changes a dish more than most cooks expect.

Full detail on gochugaru and paprika, including evidence grades and sources for every claim above.