{"schema":"askedwell-earned-page-v1","url":"https://askedwell.com/pages/what-temperature-for/water-boiling","question":"What temperature does water boil at?","short_answer":"Water boils at 212°F (100°C) at sea level (1 atm). At higher altitudes, boiling point drops: 5,000 ft = 203°F (95°C), 10,000 ft = 194°F (90°C). Simmer is 180-205°F (82-96°C) — bubbles but not rolling. Pure water + atmospheric pressure determine the exact point.","long_answer":"Water boiling is the most fundamental kitchen temperature, but it varies based on altitude, atmospheric pressure, and what's dissolved in the water. The \"212°F = boiling\" rule is true ONLY at sea level with pure water and standard atmospheric pressure. Understanding the variables matters for cooking, canning, sterilization, and baking.\n\n**The standard boiling point:**\n\n- **Sea level (0 ft elevation), 1 atm pressure, pure water:** 212°F (100°C)\n- Defined as: vapor pressure of water = surrounding atmospheric pressure\n- At this point, liquid → gas transition happens throughout the water (rolling boil)\n\n**The altitude effect (most important variable):**\n\nAtmospheric pressure decreases with altitude. Lower pressure = water needs less heat to boil. Approximation: **boiling point drops ~1°F per 500 ft of altitude gain**.\n\n| Altitude | Boiling point | Common locations |\n|---|---|---|\n| 0 ft (sea level) | 212°F (100°C) | NYC, LA, Boston, Miami |\n| 1,000 ft | 210°F (99°C) | Most US cities |\n| 2,000 ft | 208°F (98°C) | Salt Lake City foothills |\n| 3,000 ft | 206°F (97°C) | Albuquerque |\n| 5,000 ft | 203°F (95°C) | Denver, \"Mile High City\" |\n| 7,500 ft | 198°F (92°C) | Aspen, mountain ski towns |\n| 10,000 ft | 194°F (90°C) | High-altitude hiking |\n| 14,000 ft | 186°F (86°C) | Mt. Whitney summit |\n| 29,000 ft | 158°F (70°C) | Everest summit |\n\n**What this means for cooking:**\n\nAt high altitudes, water boils at lower temperatures, so foods take longer to cook. At 5,000 ft (Denver):\n- Pasta: 1-2 minutes longer to al dente\n- Hard-boiled eggs: 12-14 min instead of 10\n- Rice: needs more water, longer time, or pressure cooker\n- Boiling meat / blanching vegetables: noticeably longer\n- Canning: requires longer processing time or higher temperatures\n\nAt 7,500 ft+, baking also changes (lower air pressure affects rising — but that's separate from boiling).\n\n**Pressure effect (pressure cookers):**\n\nPressure cookers raise the boiling point by trapping steam:\n- 15 psi pressure: water boils at **250°F (121°C)**\n- 10 psi: 240°F (115°C)\n- 5 psi: 227°F (108°C)\n- This is why pressure cookers cook 2-3× faster than regular pots\n\nConversely, vacuum chambers (sous vide circulators that pull vacuum) drop boiling points dramatically.\n\n**Dissolved solutes effect:**\n\n- **Salt:** 1 tsp salt per quart raises boiling point ~0.3°F — negligible for cooking\n- **Sugar:** 1 cup sugar per quart raises boiling point 1-2°F — noticeable in candy-making\n- **Heavy syrup at 220°F (sea level)** = 6°F above water boiling = sugar concentration ~50% by weight\n- This is why candy-making relies on temperature, not time\n\n**Simmer vs. boil (the chef distinction):**\n\n- **Hard rolling boil:** 212°F (sea level), continuous large bubbles bursting at surface\n- **Boil:** 212°F, bubbles continuously at surface\n- **Simmer:** 180-205°F (82-96°C), small bubbles, gentle motion\n- **Bare simmer (poach):** 160-180°F (71-82°C), barely moving, isolated bubbles\n- **Poach (eggs):** 180-190°F (82-88°C), no bubbles to surface, very gentle motion\n\n**Why simmer not boil for stocks:**\n\nA rolling boil at 212°F:\n- Emulsifies fat into water (cloudy stock)\n- Breaks down delicate proteins\n- Can make meat tough (denaturing proteins quickly)\n- Loses delicate flavors via faster evaporation\n\nSimmer at 180-200°F:\n- Fat stays separate (skimmable for clear stock)\n- Proteins denature gently\n- Meat tenderizes vs. toughens\n- Delicate flavors preserved\n\n**Temperature ranges for water-based cooking:**\n\n| Method | Temperature | Application |\n|---|---|---|\n| Rolling boil | 212°F | Pasta, blanching, canning |\n| Boil | 200-212°F | Steam vegetables, vigorous reduction |\n| Hot simmer | 195-205°F | Stews, braises, slow reduction |\n| Simmer | 180-195°F | Stocks, broths, poaching meat |\n| Hot poach | 170-180°F | Delicate fish, custard cooking |\n| Cold poach | 150-170°F | Eggs, delicate proteins |\n| Sous vide | 120-185°F | Precision cooking |\n| Warm hold | 130-150°F | Food safety zone for holding |\n\n**Boiling point of other common liquids (cooking reference):**\n\n| Liquid | Boiling point |\n|---|---|\n| Water | 212°F (100°C) |\n| Milk | ~212°F (proteins scald at 180°F+) |\n| Heavy cream | ~218°F (slightly higher than water) |\n| Wine | 173-175°F (alcohol boils off at 173°F) |\n| Beer | ~170°F (alcohol component) |\n| Pure ethanol | 173°F (78°C) |\n| Olive oil | 570°F (300°C) — see deep frying |\n| Maple syrup (at consistency point) | 219°F (104°C) at sea level |\n| Honey | varies widely — 220-235°F |\n\n**Common altitude-cooking adjustments:**\n\n- **Boiling water for pasta at 5,000 ft:** add 1-2 min cooking time\n- **Eggs at altitude:** 12-14 min for hard boiled (vs. 9-10 sea level)\n- **Rice cooker at altitude:** add extra water, extra time, or use pressure cooker\n- **Canning at altitude:** longer processing time per USDA charts (essential for safety)\n- **Boiled potatoes:** noticeably longer at altitude\n\n**Don't:**\n- Assume water boils at 212°F regardless of location\n- Confuse \"rolling boil\" with \"simmer\" for delicate cooking\n- Cook meat at rolling boil (toughens proteins)\n- Use less time for high-altitude boiling (food won't be safe or cooked through)\n- Try to \"boil away\" alcohol completely (some alcohol can persist even with long simmering)\n\n**Common mistakes:**\n\n- **High altitude under-cooking:** assume sea-level times; food undercooked\n- **Stock turning cloudy:** boiled too vigorously instead of simmering\n- **Watery sauce:** confused simmer (200°F) with boil (212°F), didn't reduce\n- **Tough meat in soup:** rolling boil instead of gentle simmer\n\n**Cross-reference:** see /pages/how-to-convert/celsius-to-fahrenheit for temperature conversions + /pages/what-temperature-for/cooking-chicken for cooking temperatures + /pages/how-long-does/cooking-rice for altitude-affected timing.\n\nMost published references (NIST Chemistry WebBook, Harold McGee \"On Food and Cooking\", USDA canning guides, Modernist Cuisine, J. Kenji López-Alt \"The Food Lab\") converge on 212°F sea-level baseline with altitude/pressure/solute variations as documented above.","duration_iso":"PT0M","ranges":[{"condition":"Sea level (standard)","duration":"212°F (100°C)"},{"condition":"Denver / 5,000 ft","duration":"203°F (95°C)"},{"condition":"10,000 ft","duration":"194°F (90°C)"},{"condition":"Pressure cooker (15 psi)","duration":"250°F (121°C)"},{"condition":"Simmer","duration":"180-205°F (82-96°C)"},{"condition":"Bare simmer / poach","duration":"160-180°F (71-82°C)"}],"variables":[{"name":"Altitude","effect":"Boiling point drops ~1°F per 500 ft elevation gain"},{"name":"Atmospheric pressure","effect":"Lower pressure = lower boiling point (vice versa for pressure cookers)"},{"name":"Dissolved solutes","effect":"Salt: negligible effect; sugar: 1-2°F rise per cup per quart (matters in candy)"},{"name":"Boil intensity","effect":"Rolling boil (212°F) vs. simmer (180-200°F) — choose based on what you're cooking"},{"name":"Pressure cooker setting","effect":"15 psi = 250°F; 10 psi = 240°F; 5 psi = 227°F"}],"sources":[{"label":"NIST Chemistry WebBook (Water Properties)","url":"https://webbook.nist.gov/chemistry/","note":"Official US scientific reference for boiling points at varied conditions"},{"label":"Harold McGee, \"On Food and Cooking\"","note":"Scientific framework for water-based cooking and altitude effects"},{"label":"USDA Complete Guide to Home Canning","url":"https://nchfp.uga.edu/publications/publications_usda.html","note":"Altitude-adjusted processing times for safe canning"},{"label":"J. Kenji López-Alt, \"The Food Lab\"","note":"Simmer vs. boil + altitude cooking practical guide"}],"faq":[{"question":"Why does water boil at a lower temperature at high altitude?","answer":"Atmospheric pressure decreases with altitude. At sea level, atmospheric pressure (~14.7 psi) pushes down on water — water needs to reach 212°F before vapor pressure overcomes that. At 10,000 ft, atmospheric pressure is only ~10 psi, so water needs less heat (only ~194°F) to overcome it. Less pressure = lower boiling point."},{"question":"What is the difference between simmer and boil?","answer":"A boil is 212°F (sea level) with continuous large bubbles bursting at the surface. A simmer is 180-205°F (82-96°C) with small bubbles and gentle motion — much less vigorous. Simmering is gentler on delicate ingredients (stocks, custards, meat). Boiling is for pasta, blanching, and aggressive reduction. The difference matters for texture and clarity."},{"question":"Does salt make water boil faster?","answer":"No — counterintuitively, salt slightly raises water's boiling point (the salt increases boiling temperature by ~0.3°F per teaspoon per quart). However, salty water takes ever-so-slightly longer to reach boiling. The main benefit of salting pasta water is flavor, not boiling speed. The \"salt boils water faster\" myth is wrong; cooking time changes are negligible."}],"keywords":["water boiling temperature","water boiling point altitude","temperature water boils","simmer vs boil temperature","boiling point chart"],"category":"cooking","date_published":"2026-05-20","date_modified":"2026-05-20","license":"CC-BY-4.0","attribution":"https://askedwell.com"}