Description
Reviews
| Brand | - |
| Category | Robotics / STEM Teaching Tools / Sensors |
| Origin | - |
| Model Number | AHT21B |
| Communication Interface | I2C |
| Operating Voltage | 1.8V - 3.6V DC |
| Temperature Range | -40°C to +85°C |
| Humidity Range | 0% to 100% RH |
| Temperature Accuracy | ±0.3°C |
| Humidity Accuracy | ±2% RH |
| Response Time | < 5 seconds |
| Package Type | DFN Package |
| Application | IoT, HVAC, Smart Home |
Anonymous
Mar 30, 2026
Rating: 5/5
Best in class for the price
Compared to other sensors in this price range, the AHT21 offers superior response time and accuracy. Will definitely buy more for future projects.
Anonymous
Mar 16, 2026
Rating: 5/5
Excellent anti-interference performance
I tested this in a noisy electrical environment and the readings remained stable. The strong anti-interference claim seems accurate based on my tests.
Anonymous
Mar 15, 2026
Rating: 4/5
Solid sensor module
Easy to integrate using standard libraries. The form factor is compact which helped fit it into my small enclosure. Works as advertised.
Anonymous
Mar 12, 2026
Rating: 5/5
Reliable for plant monitoring
Using three of these in my automated greenhouse system. They have been running 24/7 for a month without any drift or failures. Great value for money.
Anonymous
Mar 08, 2026
Rating: 5/5
Perfect for my weather station project
The AHT21 module works flawlessly with my ESP32 setup. The I2C communication is stable and the readings are consistent with my reference meter. Highly recommended for DIY enthusiasts.
Anonymous
Mar 07, 2026
Rating: 4/5
Good accuracy, fast shipping
Arrived quickly and well-packaged. The sensor responds very fast to changes in humidity. Only giving 4 stars because the documentation could be slightly more detailed for beginners.
Q: Is this module compatible with Arduino Uno?
A: Yes, the AHT21 uses standard I2C communication and is fully compatible with Arduino Uno. You will need to connect the SDA and SCL pins accordingly.
Q: Can this sensor be used outdoors directly?
A: The module itself is not waterproof. For outdoor use, you must house it in a breathable, weather-proof enclosure to protect the electronics while allowing air flow.
Q: What is the maximum cable length recommended for I2C connection?
A: For reliable I2C communication, we recommend keeping the cable length under 20cm. If longer distances are required, please use an I2C extender or buffer.
Q: What is the power consumption in sleep mode?
A: The AHT21 features low power consumption. In sleep mode, it draws less than 0.5µA, making it ideal for battery-powered applications.
Q: Does this come with a library for Raspberry Pi?
A: While we do not provide a proprietary library, the AHT21 is supported by many open-source Python libraries available on GitHub for Raspberry Pi.
Over-Toilet Storage Rack Wall-Mounted No-Drill Bathroom Multi-Function Organizer for Toilet Essentials
$20.50
Kang Kati Gardenia Tea Scented Candle Gift Set – Long-Lasting Fragrance, Elegant Birthday Gift for Her
$35.10
Safety Self-Locking Lifting Hook with Adjustable Chain for Hoisting and Rigging
$140.00
Thickened Mobile Phone Waterproof Case, Waterproof Box, Sealed Container, Pressure-Resistant Box, EDC Drop-Proof Storage Box for Outdoor Travel
$12.00
Commercial Heated Display Cabinet for Crispy Pork Belly, Roast Chicken, and Cantonese BBQ - Constant Temperature Warmer for Peking Duck
$1,394.00
Mejiang Baohong Watercolor Line Art for Beginners, Coloring Book with Colored Pencils and Markers, Cat Letter Theme
$29.70
Shanghai Huamei Hair Transplant, Solution for Hair Loss, Thinning, and Density Enhancement
$6,750.00
New Direct Sale Nanda Silicone Rubber 704 Battery Fixative Adhesive Panel Light Special Glue Photovoltaic Solar Sealant
$25.85
Yonghe Hair Transplant: Top Scalp Density Enhancement (2000+ Units Fixed Price)
$33,800.00
No-Drill Bathroom Storage Rack – Toilet Paper Organizer for Dorms and Restrooms
$22.16
Premium Metallographic Polishing Cloth – White Short-Pile Velvet for Mirror Finish Grinding by Goral
$35.00
Rock Guitar Hell Training: Electric Guitar Textbook and Tutorial by Shinichi Kobayashi, Beginner to Intermediate Chinese Guitar Book and Sheet Music
$58.69
Aromatherapy Candle Resin Jelly Wax Strawberry Silicone Mold, Large Squishy Handmade Soap DIY Material
$1.90
Liboer Drill-Free Security Camera Mount & Router Shelf – Adhesive-Free Wall Bracket for 360 PTZ Cameras and Sockets
$21.90
City Hunter Theme Song Mr. Chui Saxophone Three-Piece Precise Transcription Service
$16.00
![[Deposit Group 12] New Colors: Hugging Bear Matte Low-Mid Heel Lolita Shoes - Sheep Puff with Bear Buckle](https://www.gosteppe.com/cache/small/product/268946/legacy-main-23070b08b8901297c3f91d93.webp)
[Deposit Group 12] New Colors: Hugging Bear Matte Low-Mid Heel Lolita Shoes - Sheep Puff with Bear Buckle
$38.00
Handcrafted Peach Wood and Brass Baby Rattle - Non-Toxic Paint-Free Teething Toy for Infants
$32.00
Car Tire Stone Removal Hook - Debris Cleaning Tool for Wheels
$6.19
Ceramic Rabbit Egg Holder – Creative Irregular Egg Stand for Breakfast or as a Decorative Gift
$33.82
Toilet Tank Side Shelf Bathroom Storage Rack No-Drill Organizer for Bathroom Essentials
$10.40
No-Drill Over-Toilet Storage Rack for Bathroom Restroom Organizer
$8.90
Artsneak Blending Stump for Oil Pastels, Dual-Tip Sponge Brush Art Student Painting Tool Set, Washable and Crumb-Free
$14.20
75X100 Imitation Inkjet Transfer Steel Plate for Date Coding - Custom Logo and Trademark Available
$38.00
Lint-Free Cloth 1009DLE/SLE - Straight/Net Weave for UV Printhead, Screen, Lens Cleaning, Industrial Wiping Cloth
$10.80
Pirelli PZ4 Tires, Sizes 235/245/255/265/285/40/45/50/55 R19/R20/R21/R22
$350.00
Wooden Plaque Carved Signboard for Business Opening, Antique-Style Shop Entrance Header, Custom Engraved Solid Wood Couplets MWU
$182.96
Kumho ES01 Car Tires: Sizes 155/165/175/185/205 with Aspect Ratios 55/60/69 and Rim Diameters 14/15/16/17
$458.00
Mont Marte Paint Brushes, Creative Children's Painting Brush Set (3 Pieces), Tempera Brush Kit for Kids
$6.50
Baohong Watercolor Paper 300g 8K/4K - Wood Pulp A1/A3/K3 350g Fine/Coarse Grain for Watercolor and Oil Pastels 4K
$4.00
Imported IK7 Linear Bearing LM 162837 203242 254059 304564 3552O0 UU
$96.00
![[Trial Pack] Xianlang Complete Cat Treat Sticks Meal Packs Main Course Cans Freeze-Dried Cat Food Sample Snacks Gift Set](https://www.gosteppe.com/cache/medium/product/208273/legacy-main-9ec245ebf781f65a434ba854.webp)
