

🔧 Calibrate like a pro, never second-guess your humidity again!
The Boveda One-Step Hygrometer Calibration Kit offers a foolproof, maintenance-free method to calibrate any digital or analog hygrometer with a stable 75% relative humidity environment. Using a reusable airtight bag and a lab-accepted humidity standard, it delivers precise calibration results in just 24 hours, lasting up to a year for multiple recalibrations—perfect for professionals demanding accuracy and reliability.











| ASIN | B000A3UBLA |
| Brand | Boveda |
| Colour | Brown |
| Customer Reviews | 4.5 4.5 out of 5 stars (3,207) |
| Date First Available | 19 Nov. 2010 |
| Item Weight | 13.6 g |
| Material | Plastic |
| Model Number | CAL75-SM |
| Product Dimensions | 11.43 x 22.86 x 0.64 cm; 13.61 g |
| Runtime | 24 hours |
| Special Features | Two-Way Humidity Control | Safe to Touch items | Adds/Removes Moisture | Preserves Aroma, Flavor & Freshness | Long Term & Short Term Storage | Replace Every 3 Months |
T**M
Excellent
I'm in the process of designing a product that measures the temperature and humidity of beehives. There are plenty of temperature sensors on the market that are cheap and accurate, but humidity sensors are generally pretty expensive in comparison and, as I've discovered, wildly inaccurate. Having purchased a sensor that I had some confidence in, I needed to test it. I created my own testbed, with very accurate control of temperature, but I needed a way to accurately define a level of humidity. There are a plethora of YouTube vids on the subject demonstrating how this can be achieved using a home-made salt solution in a bottle cap, but even having purchased some lab-grade sodium chloride and distilled water my results were all over the place. It was while I was doing more research along these lines when I can across some adverts for Boveda products in relation to maintaining the humidity in humidors, a cupboard for cigars. Looking at the Boveda website I discovered that they produce larger product packs for cigars, but also produce smaller packs with high tolerance chemical solutions that can be used for hygrometer (an instrument used for measuring the amount of humidity and water vapour in the atmosphere) calibration and purchased a pack. The Boveda One-Step Hygrometer Calibration Kit allows a high degree of reliability, with a high degree of accuracy simply by placing the hygrometer, or in my case the sensor, in a small airtight container. The kit comes complete with an air-tight plastic bag and the Boveda humidity pack. To use it, you just put the device to be tested in the bad and let the humidity in the bag settle for 12 hours or so, it's as simple as that. In my case, I placed the sensor in a small bag, sealed the bag around the wires from the sensor and placed the whole pack into my chiller. At a consistent 21.5 DegC (+/- 0.3 DegC), I let the sensor soak for a day and then analysed the results. Long story short then, the results where excellent. Incredibly stable humidity results, at exactly the level I was expecting, well within the tolerances stated by Bovida and the sensor I was calibrating during my experiments. I certainly won't be mucking about with salt solutions any more. My only regret is that I've spent a fair amount of money of lab-grade chemicals and that my better half is getting peeved with the 1Kg of salt that's taking up cupboard space. Still, I guess I can use it on my fish & chips?
A**W
Perfect Calibration for Small Hygrometers
This is a must have for anyone wanting to check and adjust a small hygrometer. Very easy to use and gives reliable results. Even if your hygrometer is not adjustable you can at least see if it is in error and mentally compensate to get a true RH reading.
A**R
Works well.
I got this to measure the humidity for a cigar humidor. Easy to connect to Bluetooth. I calibrated the humidity and it was spot on with no adjustments needed.
D**D
Nice to find a low cost standard for checking humidity sensors.
Going back to first principles in a standard package - it was brilliant for a small wireless humidity sensor. I bought a pack of low and high RH and was able to check two sensors at low and two sensors at high. I have not yet swapped the sensors to do both sets of readings but would seem to be easy to do. Only complaint is that I would like a larger plastic sleeve in order to test larger sensors. And what to do about sensors that have wire connections to a controller?
S**E
Great way to get it right.
This is the 4th time I have used this kit. I buy a new one every time I set a humidore up for a friend. It is suprising how off some hydrometer are. This works great every time to get them dialed in.
T**S
Really pleased with this
Really pleased with this, allowd me to easily calibrate my hygro no bother and once done it doubled as a mini humidor for a couple of junior coronas I had kicking about so win win.
J**C
The bag is too small
My wife binned this by accident, it was a touch too small anyway. I now just use any zip lock bag and buy the packs separately.
D**R
Essential for Hygrometer & Good Cigars
Should be sold with every hygrometer! Mine was out by 2% which was within the expected tollerance but now dialled in. Sorted.
J**.
avec ce produit mon capteur indiquait 41%RH au lieu de 32%RH Avec le test pâte de sel (sel + eau) dans un bocal : 74%RH. Donc pas fiable.
S**A
I use humidity sensors in terrariums. With high humidity sensors will raise the humidity as much as 10% in only a few months. For me accuracy is very important. The Boveda calibration kit worked very well for me bringing the calibration within 1% of the 75% target. I especially like the size as I can calibrate more than one sensor at a time. Depending on the size of your sensors they will fit 2 or more. This best part is the accuracy and ease of use.
R**.
no recomiendo comprar los kits de calibracion. el kit que yo compre de 32% HR ya tenia un año de haber caducado. Y la bolsa para meter el higrometro es muy chica. Mejor recomiendo comprar las Bovedas de 58% y 75% HR y calibrar tu higrometro con ellas. Puedes usar bolsas de ZipLock.
P**A
75%と32%をそれぞれ2つづつ購入。75%は他の方も指摘されている通り、水分が抜けて固まっていました。32%は、水分も保たれた状態でしたが、4つある湿度計が30時間放置して41%ーから43%を示すので海外レビューにもあるように32%には保てないようです。家庭では精製水に塩を解けなくなるまで混ぜて、それをジップロックに入れて75%の調整した方が確実です。
J**Z
Está bien
Trustpilot
2 weeks ago
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