Sign Up to Use the Degree Days.net API

The Degree Days.net API (Application Programming Interface) will give your software automated access to data from our service, including data going further back in time than our free website allows.

Sign up for any of the plans below to get API access keys. You can enter your API access keys into compatible third-party software to enable it to automatically fetch degree days on your behalf. Or you can use your API access keys to build degree days into your internally-developed software systems.

The following location-limited plans enable software to fetch regular data updates from a consistent set of locations:

1 Location	3 Locations	6 Locations	10 Locations
$9/month	$19/month	$29/month	$39/month

The following unlimited-location plans offer greater flexibility and access to larger quantities of data:

Basic	Standard	Plus	Premium
$49/month	$195/month	$695/month	$1,995/month
Unlimited locations	Unlimited locations	Unlimited locations	Unlimited locations
Up to 100 requests per hour*	Up to 500 requests per hour*	Up to 2,500 requests per hour*	Up to 10,000 requests per hour*
For individuals using tools to access custom data, or for automated applications with low load.	For small teams needing flexible bulk data access, or for automated applications with modest load.	A higher rate limit for greater data-calculation throughput and flexibility of access.	Our highest rate limit for companies needing large quantities of data or maximum flexibility of access.

* Rate limits are set in terms of the maximum number of "request units" allowed in any given hour. Simpler requests, such as a request for up to a year's worth of data from a specific weather station, count as one request unit. But some requests require more processing than others, and count as more than one request unit against the rate limit. This is explained in more detail below.

We use a popular e-commerce service provider called FastSpring to handle billing for us - the "Sign Up" buttons above all lead to FastSpring's secure website where you can enter your credit card details and gain instant access to the Degree Days.net API.

FastSpring's payment system accepts Visa, MasterCard, American Express, Discover, and PayPal.

FastSpring is run by Bright Market LLC, a US company headquartered at 11 West Victoria Street, Suite 207A, Santa Barbara, California 93101.

Cancellation is straightforward, and you can cancel at any time without penalty. After cancellation you will not be billed again, and you can continue to use the API until the end of the month that you've already paid for.

Requests and responses - how the API works

To make sense of the pricing, you need to understand roughly how the API works. You don't need to be technically minded.

Your software sends a request to the API, specifying what data you want, and for what location. For example, you might request 12 months of 65F-base-temperature degree days from KNYC (a weather station in Central Park, New York).
The API will send back a response containing the data you requested or a failure code if the data could not be generated. KNYC has good temperature data so a failure for that station would be unlikely, but not all stations have good data.
You can fetch more data by sending more requests. If you want data for 800 different locations, just make 800 requests - one for each location.
You can fetch up to 100 sets of data with a single request, provided they are all from the same location. For example, you might want to fetch HDD and CDD at 50 different base temperatures each.
You can specify the location that you want data for as a weather station ID or as a geographic location (either a longitude/latitude point or a postal/zip code). If you specify a geographic location, the API will choose a nearby weather station automatically and generate your data using that.

Rate limits and request units

Calculating degree days is an intensive process. A typical request for data requires our system to access and churn through many thousands (often millions) of temperature readings. The resulting degree-day figures are simple, but the process that generates them is anything but.

Rate limits enable us to manage the processing load and keep our service running efficiently and sustainably. They make it possible for us to offer account plans to suit a wide range of use cases and budgets. And they are easy for other software systems to work with: if a system reaches its rate limit in any given hour, it only has to wait until the next hour to make requests again.

When you choose your hourly rate limit, you are effectively reserving a slice of our system's data-generation capacity for use when you need it.

Each API request that you make will bring you closer to your hourly rate limit. If you reach your rate limit in any given hour, you will need to wait until the next hour before making more requests.

The rate limit works with "request units". Some requests count as just one request unit, but requests that require more processing (e.g. those that cover more than a year's worth of data) count as more than one request unit.

Working out how many request units a request will count as:

All API requests count as 1 request unit at a minimum.
For a request for a single set of data, it's 1 request unit for each year of data coverage. For example, a request for a year's worth of data counts as 1 request unit, 2 years counts as 2 request units, 3 years as 3, 4 years as 4, and so on.
You can fetch up to 100 data sets for a location in a single request (e.g. HDD and CDD in 50 different base temperatures each). For 100 data sets multiply the number from step b by 5; for between 1 and 100 data sets the multiplier follows a simple sliding scale between 1 and 5.
Add on 1 extra request unit if you are fetching data for a "geographic location" (i.e. if you are specifying the location you want data for as a longitude/latitude or postal/zip code instead of using a specific weather-station ID).

Note that additional request units are only added if the request goes through successfully. If, for example, you request 10 years of data from a weather station (10 request units in total), but only 5 years of data are available, then your request will only count as 5 request units. If you specify a geographic location for which no good data can be found, then no additional request units will be added for that request.

Rate limits on location-limited account plans

The location-limited account plans are primarily limited in terms of the number of locations that they can be used to fetch data from. Allowed locations are set automatically as requests for data are made (allowing for a limited number of changes over time).

The location-limited plans are also rate limited in terms of the number of requests that can be made per hour. These limits are unlikely to be reached by well-programmed software using the API for typical use cases.