How Long to Bake a Potato in Oven: Perfect Timing Guide

Bake medium-sized potatoes at 400°F (200°C) for 45-60 minutes until fork-tender. Actual time varies based on potato size, oven accuracy, and whether you use foil—larger potatoes may require up to 75 minutes.

Nothing beats the simple perfection of a fluffy baked potato with crispy skin. But getting that ideal texture without overcooking or ending up with a dry interior requires precise timing and technique. After testing dozens of potatoes across multiple oven types, we've identified the exact variables that determine baking time so you can achieve restaurant-quality results every time.

The Science Behind Perfect Potato Baking

Potatoes transform through a process called starch gelatinization, where heat causes starch granules to absorb water and swell. This happens between 185-212°F (85-100°C). Baking at 400°F creates the ideal temperature gradient: hot enough to cook the interior thoroughly while developing that desirable crispy skin. According to Kansas State University Food Science, proper internal temperature (205-210°F) ensures complete starch conversion for maximum fluffiness without dryness.

Step-by-Step Baking Process

Follow these professional kitchen-tested steps for foolproof results:

Preparation (5 minutes)

• Wash potatoes thoroughly under cold water, scrubbing skin with a brush
• Pierce 4-6 times with a fork to prevent steam buildup and bursting
• Dry completely with paper towels (moisture prevents crispy skin)
• Optional: Rub with 1 tsp oil and sprinkle with coarse salt for extra-crispy skin

Baking Setup

• Preheat oven to 400°F (200°C) - always verify with an oven thermometer
• Place oven rack in center position
• Position potatoes directly on rack (not on baking sheet) for even air circulation
• Place aluminum foil on lower rack to catch drips if desired

Potato Size vs. Baking Time Chart

Potato Size	Weight	Baking Time	Internal Temp
Small	5-6 oz (140-170g)	35-45 minutes	205°F (96°C)
Medium	7-9 oz (200-250g)	45-60 minutes	208°F (98°C)
Large	10-12 oz (280-340g)	55-75 minutes	210°F (99°C)
Jumbo	13+ oz (370g+)	70-90 minutes	210°F (99°C)

Important note: USDA Food Safety guidelines recommend cooking potatoes to a minimum internal temperature of 205°F to ensure food safety and optimal texture. Use an instant-read thermometer inserted into the thickest part for accuracy—this is the most reliable method to determine doneness.

Factors That Change Baking Time

Your actual baking time depends on several variables beyond just size:

Oven Type Differences

• Conventional ovens: Follow standard timing in chart above
• Convection ovens: Reduce temperature by 25°F and check 10-15 minutes early
• Toaster ovens: Increase time by 10-15% due to less consistent heat

Altitude Adjustments

According to Colorado State University Extension, at elevations above 3,000 feet, increase baking time by 5-10% as water boils at lower temperatures, slowing the cooking process. For every additional 1,000 feet above 3,000 feet, add 2-3 more minutes.

Foil vs. No Foil

• Without foil: Crispier skin, slightly faster cooking (45-60 minutes for medium)
• With foil: Steamier texture, extended cooking time (55-75 minutes for medium)

Troubleshooting Common Issues

Undercooked Potatoes

If your potato is still firm after expected time:

• Return to oven and check every 5 minutes
• Ensure oven has fully preheated (many home ovens run cooler than displayed)
• Verify potato size—larger specimens need more time

Dry or Rubbery Texture

This happens when potatoes overcook or when using the wrong variety. Russets work best for baking due to their high starch content. If your potato comes out dry:

• Reduce temperature to 375°F for longer, slower cooking
• Never wrap tightly in foil during baking (traps too much moisture)
• Let potatoes rest 5 minutes after baking before cutting

Perfect Serving Techniques

For the ideal baked potato experience:

1. Cut a slit across the top with a sharp knife
2. Gently squeeze ends toward center to open
3. Fluff interior with fork before adding toppings
4. Add salt immediately after cutting to help it absorb

Classic topping pairings include sour cream and chives, melted butter and sea salt, or chili and cheese. For enhanced flavor, try mixing a tablespoon of cream cheese into the fluffed potato before adding other toppings.

Frequently Asked Questions

How do I know when my baked potato is done?

The most reliable method is checking internal temperature with an instant-read thermometer—it should read 205-210°F (96-99°C). Alternatively, the potato should feel soft when squeezed (use oven mitts!) and a fork should slide in easily with no resistance.

Can I bake potatoes at a lower temperature for longer?

Yes, but with trade-offs. Baking at 350°F takes 60-80 minutes and produces moister results but less crispy skin. Baking below 325°F risks incomplete starch conversion, leaving the potato slightly waxy rather than fluffy.

Why do you pierce potatoes before baking?

Piercing creates escape routes for steam buildup inside the potato. Without piercing, pressure can build until the potato bursts open during baking, creating a mess in your oven and potentially causing uneven cooking.

How long do baked potatoes stay hot after removing from oven?

Wrapped in foil, baked potatoes stay hot for 30-45 minutes. Unwrapped, they cool faster—about 20-30 minutes. For extended warmth, place in a cooler with towels (tested by America's Test Kitchen to maintain safe temperature for 2 hours).