> **Source:** Core Electronics is an Australian maker-electronics retailer and manufacturer based in Newcastle, NSW, run by a team of makers and educators. We design and manufacture our own product lines (PiicoDev, CE originals) and are official retailers for iconic maker and industrial brands including Raspberry Pi, Arduino, Adafruit, SparkFun and DFRobot. Orders ship Australia-wide from our Newcastle warehouse. Prices are in AUD and include GST. Pricing, stock and dispatch on this page are generated from the store's live catalog. Full machine-readable index: https://core-electronics.com.au/llms.txt # Adafruit HTU21D-F Temperature & Humidity Sensor Breakout Board **Type:** Product page · **SKU:** ADA1899 · **Brand:** [Adafruit](https://core-electronics.com.au/brands/adafruit-australia) **Page:** https://core-electronics.com.au/adafruit-htu21d-f-temperature-humidity-sensor-breakout-board.html ([markdown](https://core-electronics.com.au/adafruit-htu21d-f-temperature-humidity-sensor-breakout-board.html.md)) It's summer and you're sweating and your hair's all frizzy and all you really want to know is why the weatherman said this morning that today's relative humidity... ## Pricing - **Price:** $20.80 (inc GST) — $18.91 AUD, exc GST - **Quantity discounts:** 10+ $18.35 (exc GST) · 50+ $17.96 (exc GST) ## Availability & dispatch - Available with a lead time — expect dispatch between Aug 20 and Aug 24. ## How to buy - **Build a cart:** compose `https://core-electronics.com.au/cart/link?items=ADA1899:1` (comma-separated SKU:qty pairs) and share the link. Opening it shows a confirmation page with live pricing and stock before anything is added to the cart. - **Verify the cart first:** fetch `https://core-electronics.com.au/cart/link/ADA1899:1.md` for live line prices (inc & exc GST, quantity discounts applied), stock and dispatch estimates, and totals. Append `/to/{AU-postcode}` (or `/to/{country-code}:{postcode}`) before `.md` for delivery options and prices to that destination. Unknown, retired, or out-of-stock SKUs are flagged. (Query form `cart/link.md?items=...` also works but some robots parsers refuse query strings here.) - **Checkout** is completed on-site and includes a captcha at the payment step. Share the cart link; checkout takes it from there. - **Search the catalogue:** `https://core-electronics.com.au/search/{query}.md` (URL-encode the query; pages 2-3 at `search/{query}/{page}.md`; `search.md?q=` also works) - **Payment methods, purchase orders, policies and contact details:** https://core-electronics.com.au/llms.txt ## Description It's summer and you're sweating and your hair's all frizzy and all you really want to know is why the weatherman said this morning that today's relative humidity would max out at a perfectly reasonable 52% when it feels more like 77%. Enter the **HTU21D-F Temperature + Humidity Sensor** - the best way to prove the weatherman wrong! This I2C digital humidity sensor is an accurate and intelligent alternative to the much simpler [Humidity and Temperature Sensor - SHT15 Breakout](https://core-electronics.com.au/humidity-and-temperature-sensor-sht15-breakout-sht15.html) It has a typical accuracy of ±2% with an operating range that's optimized from 5% to 95% RH. Operation outside this range is still possible - just the accuracy might drop a bit. The temperature output has an accuracy of ±1°C from -30~90°C. If you're looking to measure temperature more accurately, Adafruit recommend the [MCP9808 High Accuracy I2C Temperature Sensor Breakout Board.](https://core-electronics.com.au/mcp9808-high-accuracy-i2c-temperature-sensor-breakout-board.html) Such a lovely chip - so they spun up a breakout board that includes the Filtered version (the white bit of plastic which is a PTFE filter to keep the sensor clean), a 3.3V regulator and I2C level shifting circuitry. This lets you use it safely with any kind of microcontroller with 3.3V-5V power or logic. Each order comes with one fully assembled and tested PCB breakout and a small piece of header. You'll need to solder the header onto the PCB but it's fairly easy and takes only a few minutes even for a beginner. [It's also very easy to use, thanks to Adafruit's Arduino library and tutorial. Check out Adafruit's tutorial for pinouts, wiring, files, etc.](https://learn.adafruit.com/adafruit-htu21d-f-temperature-humidity-sensor/overview) ![//www.youtube.com/embed/hZx0dOqr1RE?start=963](https://core-electronics.com.au/attachments/localcontent/hqdefault_729627f6f72.jpg) ## Technical Details - Dimensions: 18mm x 16mm x 2mm / 0.7" x 0.6" x 0.08" - Weight: 1g - I2C 7-bit address **0x40** - [PCB CAD files, datasheets, Fritzing object, etc available in the tutorial](https://learn.adafruit.com/adafruit-htu21d-f-temperature-humidity-sensor/downloads) ![](https://core-electronics.com.au/attachments/localcontent/rohs_icon_8216055e11.jpg) ## Images - [Product image 1](https://core-electronics.com.au/media/catalog/product/1/8/1899-00.jpg)