How Long to Bake a Potato at 350, 400, 425 and 450
At 350°F a medium potato takes about 75–90 minutes; at 400°F it’s roughly 60–75 minutes, and at 425–450°F expect 45–60 minutes. Start checking early if your oven runs hot or the potatoes are small.
The exact time shifts with size, whether you bake directly on the rack or in foil, how many you cook together, and starting from room temperature rather than cold. Altitude and individual ovens also vary enough to matter.
For reliable doneness, test by feel: squeeze with an oven glove or pierce with a skewer — there should be no resistance. If using a thermometer, aim for a centre of about 205–210°F (96–99°C) for fluffy flesh. This is a texture target, not a safety requirement.
Timing
| Oven Temperature | Typical Time (Medium Potato, ~200–250g) | Timer |
|---|---|---|
| 350°F (175°C) | 60–75 minutes | |
| 400°F (205°C) | 55–65 minutes | |
| 425°F (220°C) | 45–55 minutes | |
| 450°F (230°C) | 40–50 minutes |
Use this table as a starting point for medium-sized potatoes baked directly on the rack or tray. Times shorten at higher heat and lengthen for larger spuds; start checking early by piercing the centre—it should offer no resistance. Aim for an internal temperature of about 205–210°F (96–99°C) for fluffy texture. If you lack a thermometer, verify doneness when a skewer slides through easily and the skin is crisp.
What changes the time
Size or thickness
The potato’s mass is the main driver of bake time. A small 150–200 g spud cooks much faster than a large 300–400 g one, and thick russets take longer than slender varieties. Uniform size helps them finish together. Test doneness by squeezing gently (with protection) or sliding in a thin knife; it should meet little resistance. For fluffy centres, aim for an internal temperature of about 205–210°F (96–99°C). If you are baking mixed sizes, remove smaller ones as they finish to avoid overdrying.
Starting temperature — chilled, room-temperature or frozen
Cold potatoes from the fridge add noticeable minutes because the oven must first warm their core. Room-temperature tubers start cooking through sooner and brown more evenly. Frozen baked potatoes need substantially longer; heat them without thawing but expect extra time and softer skins unless finished hotter at the end. However you begin, judge by feel and probe: centre tender with no hard spots, targeting about 205–210°F (96–99°C) inside if using a thermometer. Pricking before heating reduces steam pressure regardless of starting temperature.
Equipment or altitude
Oven type matters. Fan-assisted ovens circulate hot air and often shave several minutes compared with conventional settings at the same dial. Heavy trays or preheated stones can speed contact heat, while tightly wrapping slows skin crisping. At higher altitude, water boils at lower temperatures, extending drying and softening times; plan on adding minutes and confirm with the squeeze/knife test. Because these variables shift results, rely on texture plus an internal reading of about 205–210°F (96–99°C) rather than clock-watching alone when judging completion.
How to tell it is done
Doneness depends on texture, not colour. The skin should be crisp and slightly wrinkled; the centre must yield easily when pierced with a skewer or thin knife, offering no resistance. For precision, insert an instant-read thermometer into the middle: aim for 205–210°F (96–99°C). At this range, starches have gelatinised fully, giving a fluffy interior rather than a waxy one. If you lack a thermometer, press the potato gently with tongs—it should feel soft but still hold its shape. Over-softening means water has escaped, drying the flesh.
Common mistakes
- Wrapping potatoes in foil traps steam, steaming instead of baking. This yields soggy skins and gummy interiors. Bake unwrapped directly on the rack so dry heat crisps the exterior while cooking the core evenly throughout.
- Cold potatoes from the fridge extend bake time unpredictably and can toughen the skin before the inside cooks through. Let them sit at room temperature for twenty minutes first.
- Skipping the pierce step risks bursting as internal steam builds rapidly under pressure. Stab each potato six times with a fork to vent safely during heating without losing moisture excessively.
- Using giant spuds without adjusting time leaves hard centres even when timers ding loudly. Choose uniform medium sizes around eight ounces, or add fifteen extra minutes per additional size increment carefully.
- Crowding trays blocks airflow between items, creating hot spots that char some sides whilst others remain stubbornly raw underneath entirely. Space pieces two inches apart minimum always.