Cigar Humidor Humidity and Temperature: What RH and Temp to Hold

Most cigar humidors are held between roughly 62% and 72% relative humidity, with about 65% to 70% RH the common target, at a temperature somewhere in the mid-60s to low-70s Fahrenheit. The old 70/70 rule is a starting point rather than a law, and plenty of experienced collectors deliberately settle a few points drier.

The 70/70 rule, and why collectors drift below it

70% RH at 70°F is the number most people hear first because it is easy to remember and it keeps a cigar from drying out. It is a safe default, not an optimum. The practical objection is that a cigar sitting at 70% RH often burns slower, draws tighter, and can taste damp or muted, particularly a thick ring gauge. Dropping to the mid-60s usually tightens the burn and lets more of the tobacco through.

The other reason to sit under 70% is margin. A humidor that runs at 70% has almost no headroom before it reaches the range where mold becomes a real risk, and a warm week or an over-charged humidity pack can push it there. A humidor that normally sits at 65% can drift several points in either direction and still be fine.

A practical RH reference

Treat these as approximate bands rather than hard thresholds. Wrapper, ring gauge, and how long a cigar has rested all shift where it smokes best.

Temperature matters as much as the humidity number

Temperature and relative humidity are linked, so you cannot manage one and ignore the other. Warm air holds more moisture, which means the same amount of water in a humidor reads as a lower RH when the room heats up and a higher RH when it cools. A humidor that swings with the seasons will show RH swings that have nothing to do with your humidity packs.

The bigger reason to watch temperature is tobacco beetles. Their eggs are widely understood to become active once storage gets into the high 70s Fahrenheit and warmer, which is why most guidance keeps a humidor comfortably below that and out of direct sunlight, attics, garages, and the top of a warm appliance. A stable interior room is almost always better than a spot that happens to look good.

Why humidors drift

• Seasons. Winter heating dries a room and pulls RH down; summer pushes it back up. Expect to adjust twice a year.
• New or unseasoned wood. Dry Spanish cedar absorbs moisture aggressively until it is seasoned. See how to season a new humidor.
• Over-packing. Cram a humidor full and airflow suffers, readings become uneven, and one corner can sit wetter than the rest.
• Spent humidity packs. Two-way packs stiffen as they exhaust and stop regulating well before they look obviously dead.
• Opening the lid. Frequent or lengthy openings dump conditioned air. Brief and purposeful is better than browsing.

Measure it properly

A single cheap analog hygrometer is the most common source of bad humidor decisions. Use a digital hygrometer, and if the humidor is large or oddly shaped, use two placed at different heights so you can see whether the box is actually uniform. Calibrate before you trust the number: the salt test, where the hygrometer sits in a sealed bag with damp salt and should read close to 75%, is the standard check, and any consistent offset can simply be noted and subtracted.

Then log it. One reading tells you almost nothing; a series of readings tells you whether the humidor is stable, seasonally drifting, or slowly failing at the seal. A humidor that reads 66% today and 66% last month is healthy. One that has slid from 70% to 63% over six weeks is a problem you can still catch early.