Vegetable Roasting Calculator

Pick everything going on the pan and this works out the staggered timeline — what starts first, what gets added when — so it all comes out together.

Roasting Times at 425°F

Times assume a single layer on a rimmed sheet pan, lightly oiled, cut to the size shown. Published charts vary quite a bit on these numbers — often because they're written for different oven temperatures without saying so — which is why every figure here states its temperature and cut size.

Vegetable	Cut	Time at 425°F	Group
Beets	¾" cubes	35-45 min	Dense root
Potatoes	¾" cubes	30-40 min	Dense root
Sweet potatoes	¾" cubes	25-35 min	Dense root
Carrots	½" slices	25-35 min	Dense root
Parsnips	½" slices	25-35 min	Dense root
Butternut squash	¾" cubes	25-35 min	Winter squash
Onions	Wedges	25-30 min	Medium
Brussels sprouts	Halved	20-30 min	Cruciferous
Cabbage	Wedges	20-30 min	Cruciferous
Eggplant	¾" cubes	20-25 min	Medium
Cauliflower	Florets	20-25 min	Cruciferous
Broccoli	Florets	18-25 min	Cruciferous
Bell peppers	Strips	15-20 min	Soft
Zucchini	½" rounds	15-20 min	Soft
Mushrooms	Halved	15-20 min	Soft
Cherry tomatoes	Whole	15-20 min	Soft
Green beans	Whole	12-18 min	Thin
Asparagus	Whole spears	10-15 min	Thin
Snap peas	Whole	10-12 min	Thin
Kale	Torn leaves	8-12 min	Leafy

At 400°F add roughly 15-20% to these times; at 450°F subtract roughly 15-20%. Kale is the exception — it does better around 350°F, since it burns before it crisps at high heat.

How the Timeline Works

The arithmetic is simple, but almost nobody does it in their head while holding a chopping board. Take the longest-cooking vegetable on your pan — that sets the total. Every other vegetable goes in when the time remaining equals its own roasting time.

Potatoes at 35 minutes and asparagus at 12: the potatoes start alone, and at the 23-minute mark (35 − 12) the asparagus joins them. Both finish at 35. That's it. The calculator just runs it for however many vegetables you've picked and sorts them into a running order.

Where charts elsewhere tell you to "start the hard vegetables first and add the soft ones later," this gives you the actual clock times, which is the part that decides whether dinner works.

Cut Size Beats Vegetable Type

Roasting time tracks the thickness of the piece far more than the identity of the vegetable, and this is the lever most people don't use. A potato in ¾-inch cubes takes about 35 minutes; the same potato in ½-inch cubes is closer to 25. Halve a Brussels sprout and it roasts in the time a whole one needs to merely warm through.

So if you want two vegetables to finish together and don't fancy staggering, cut the dense one smaller and the soft one chunkier. Carrots in thin coins and zucchini in thick half-moons will land within a few minutes of each other. The times in the chart above assume the cut listed beside them — change the cut and you change the time.

The Crowding Rule

The most common failure isn't timing, it's a full pan. Vegetables release a lot of water as they heat, and that steam has to go somewhere. On a crowded pan it sits between the pieces and cooks them in their own moisture — you get pale, limp vegetables no matter how long you leave them in or how hot the oven is.

Single layer, visible gaps between pieces, and a second pan rather than a taller heap. If you're running two pans, swap their rack positions halfway through, since almost every home oven has a hotter and a cooler shelf. Wet vegetables — anything just washed, or frozen — should be patted dry first, because that surface water has to boil off before browning can start at all.

Frequently Asked Questions