The Ecowitt family.

Why growers look here.

• Price. A soil probe under twenty US dollars, a room sensor near ten, a gateway near twenty. A bench, a tunnel and a field can each have a sensor for less than one professional probe.
• Nothing to wire. Each sensor runs a year or so on an AA cell and broadcasts on its own.
• The cloud is optional. Every current gateway can post its readings to an address on your own network, and works with no internet at all. That is rare at this price, and it is the reason this family is on this site.
• The radio is open in practice. The sensors broadcast one way with no pairing secret, and the open rtl_433 project has decoders for most of the family. If the company vanished tomorrow, the sensors would keep talking and open software would keep hearing them. That is the real insurance.

What it is not: calibrated, certified, or supported like professional equipment. That section is blunt about it.

Which version for your country.

Every Ecowitt sensor is sold in several radio versions. They measure the same thing and send the same message; only the carrier frequency differs. A sensor and the gateway or console it reports to must be the same version, or they will never hear each other. So this is the first decision, and it is set by where you live.

The lists below are Ecowitt’s own selling guidance (its “Recommended frequency” sheet, version 1.3, read 2026-09-18). It is not a legal ruling. Radio rules are national: your regulator decides what may transmit, and a seller in your own country is the safest sign that a version is approved there.

Your country

The antenna length is a quarter wavelength, for anyone building their own receiver. Two practical notes. Where two versions are listed, the higher band is usually the quieter one, because 433 MHz is shared with car keys, doorbells and half the gadgets in the house. And if you already own one Ecowitt device, the decision is made: match it.

The family, model by model.

Prices are single-unit US-dollar prices from Ecowitt’s own shop on 2026-09-18, to show the scale; they move, and they differ by country. The last column says how the readings can reach a place you own. Open decoder means the rtl_433 decoder for that model is linked into the FSK build of the OAT listener; that build has not yet heard a sensor, and its images are on a bench page marked unproven, so today the gateway is the route we stand behind for every model. Gateway only means nothing open decodes it.

The “open decoder” column is not typed by hand. Each model’s decoder is looked up in the list generated from the decoder library our listener is built against (commit 236c816), so the page cannot claim a model the image does not link.

Getting the readings to a place you own.

The gateways.

Ecowitt documents limits per gateway, for example sixteen soil probes and eight temperature channels on the small ones. A site with more probes than that needs a second gateway, or the listener route when it is ready.

Buying it where you live.

• Buy locally if you can. A seller inside your country has already cleared the radio version and the import. Ecowitt runs regional storefronts from its own shop, and sells on Amazon by band: 915 MHz on the US and Canadian sites, 868 MHz on the UK and German sites, 433 MHz on the Australian site.
• Check the version on the listing, every time. The same model number is sold in every band. Marketplace listings often bury it. A mismatched sensor is not faulty and will not be refunded as faulty.
• The same sensors wear other names. Froggit in Germany, Ambient Weather in the United States, Misol and others on the marketplaces. The sensors speak the same radio language. The consoles do not all offer a custom server, so if keeping data local matters, confirm that setting exists before buying a rebranded console.
• Importing directly from Ecowitt’s shop ships from China or a regional warehouse. Expect your country’s duty and tax on top, slow replacement parts, and a return policy reviewers describe as costly to use. At these prices a spare sensor is the practical warranty.
• Units are not an obstacle. The sensors send raw values; metric or imperial is a display setting, and oat-ods is metric throughout.
• Batteries. In cold climates use lithium AA cells in outdoor sensors; alkaline cells sag below freezing and the sensor drops out on the nights you most want it.

What class of instrument this is.

Consumer instruments, sold honestly as such. Typical stated accuracy is ±1 °C and ±5 % relative humidity, with no calibration certificate and no traceability. That is good enough to decide when to irrigate, whether to vent, and whether tonight is a frost night. It is not good enough for a research plot, a regulatory record, or a dispute.

• Soil moisture. The WH51 and WH52 are capacitive probes. They track wetting and drying well. The percentage they report is not volumetric water content for your soil until you calibrate it: read the probe in soil you have wetted to field capacity and again when the crop first shows stress, and irrigate between those two numbers. Soil moisture sensors explains why.
• Piezo rain. The WS85 and WS90 count raindrop impacts on a plate. Wind, drop size and light drizzle all bend the number. Ecowitt itself recommends a tipping-bucket WH40H beside a piezo array, and publishes a five-point calibration for the piezo. For irrigation decisions, trust the bucket.
• Conductivity on the WH52. We have not tested it. Treat it as a trend until someone has compared it with a meter.
• Siting beats specification. A ten-dollar sensor in a radiation shield at crop height tells you more than a precise one screwed to a sunny wall. Trust your gauge.

The company.

Ecowitt is the direct brand of Shenzhen Fine Offset Electronics, founded in 2008 in Shenzhen, China. Fine Offset has been the original design manufacturer behind a long list of weather-station brands, which is why the same sensors appear as Ambient Weather, Froggit and others, and why the open decoders name them as “Fine Offset”. It is a private company and publishes no financials. What can be observed: firmware for current sensors is still being released, the local custom-server setting has survived every product generation, and the radio messages have stayed stable for years. What cannot be promised: that a private manufacturer keeps any of that. The defence is the one this site recommends for every vendor: keep your readings in a format and a place you own, so the sensor is replaceable.