Privacy
Privacy Policy
The short version: no account and no ads. What you type stays in your browser. Visits are counted with Google Analytics only if you accept its cookies.
What is saved, and where
A few settings are saved in your browser's own storage (localStorage) on your device, so the calculators remember your room next time. They never leave your device. This is the complete list:
| Name | What it holds |
|---|---|
| vpd:theme | Light or Dark, only after you click one of the buttons. |
| vpd:consent:v1 | Whether you accepted or rejected Google Analytics cookies, so the banner does not ask again. |
| vpd:prefs:v1 | Your units (°C or °F; kPa, mbar or psi) and growth stage. |
| vpd:conditions:v1 | Your last air temperature, humidity and leaf setting, so the calculators open with your room. |
| vpd:chart:v1 | Paper size (A4 or US Letter) and whether to print one stage or all four, on the VPD chart page. |
| vpd:dehumidifier:v1 | Metric or US units, and grow room or drying room, on the dehumidifier page. |
| vpd:dli:v1 | The crop you last picked on the DLI page. |
| vpd:home:v1 | Whether you run added CO₂, and your lights-off temperature, on the homepage. |
| vpd:humidity-input:v1 | Whether you enter humidity as RH, dew point or wet bulb on the homepage. |
| vpd:wetbulb:v1 | Your psychrometer type and altitude on the wet bulb page. |
| vpd:humidifier:v1 | Metric or US units on the humidifier page. |
| vpd:fan:v1 | Feet or metres on the exhaust fan page. |
| vpd:co2:v1 | Metric or US units on the CO₂ page. |
| vpd:light:v1 | Feet or metres, and the crop, on the grow light page. |
| vpd:power:v1 | The equipment list, price and currency on the electricity cost page. |
| vpd:spacing:v1 | Feet or metres on the plant spacing page. |
| vpd:log:v1 | Readings you save in the reading log (time, temperatures, humidity, stage), up to 5,000. Delete or export them on the homepage. |
To remove them, clear this site's data in your browser settings. In a private window nothing is kept after you close it. If your browser blocks storage, the calculators still work; they just start from the defaults each time.
So the site works without a connection, your browser also keeps a copy of its pages (in its cache storage). That copy is the site itself, not anything you typed, and it is replaced when the site updates.
What is sent
Nothing you type. There are no ads, and no other site's scripts run unless you accept Google Analytics (below). The fonts are served from this site, not from a font service.
If a calculator hits an error, the error is written to your browser's developer console. Nothing is sent: automatic error reporting is switched off.
Like any website, the server that delivers these pages may keep standard access logs, such as IP address, time and page requested.
Cookies and Google Analytics
The first time you visit, a bar at the bottom of the screen asks whether we may use Google Analytics, a service from Google that counts visits. Until you click Accept, no Google script loads and no cookie is set. If you click Reject, or never choose, it stays that way.
If you accept:
- Google Analytics sets two cookies,
_gaand_ga_088F4ZFTSH, which tell one visit from another and last up to 2 years. - It sends Google the page you open (without anything after the
?in the address, so a shared result stays private), the site that sent you, your browser, device and screen size, your rough location (country and city, worked out from your IP address, which Google Analytics does not store), and actions such as scrolling to the end of a page or opening a link to another site. - It never includes the numbers you type. Google's advertising features are switched off, so the data is not used for ads.
- We see the totals in Google Analytics reports. Google handles the data under its privacy policy.
Your current choice: not made yet. You can change it at any time. If you switch to Reject, the Google Analytics cookies are deleted.