API Hub
Know what you need before making a request.
Each version states its authentication, where to find its specifications, and what has been measured, with who reported it and when.

Per version
Authentication and specifications belong to each version.
Two versions of one API may use different authentication. These facts stay with each version and name their sources.
Authentication
No authentication, API key, or user authorization is recorded for each version. A new authentication method does not change the old version’s record.
Specifications
The entry states where the specifications are, who provided them, and when they were checked.
Measurements
Every measurement includes its metric, method, conditions, unit, and date.
Sources
Each fact identifies whether it came from the provider, public data, or a community measurement. Imported data links to its source and license.
Measurements and ratings are different. Ratings reflect people’s views. Measurements state what was observed under which conditions.
Measurements
Read these five details first.
Check the metric, method, conditions, unit, and date. When comparing results, also check the outcome, subject, and coverage.
Metric
What was measured.
Method
How it was measured.
Conditions
The conditions during measurement.
Unit
The unit used for the value.
Date
When it was measured. Older results keep their dates.
Results for the same metric build a history and can be compared with other APIs in one table.
Missing data
Unknown, zero, and not applicable are different answers.
An unmeasured value is unknown, not zero. A metric that does not apply is not treated as missing data. Missing information does not become a misleading score.
Check authentication before you integrate.
Use one account to find APIs, follow version changes, and share integration experience with others.