Convert numbers between various historical numeral systems.
Convert Roman numerals to standard number notation:
Convert a decimal number to Mayan numerals:
Look up or compare major historical periods.
Find the date range associated with a historical period:
Compare historical periods:
Convert between current and historical values of US money.
Compute the current value of a historical quantity of US money:
Compute the historical equivalent value of today's US money:
Explore and visualize named family relationships.
Compute a family relationship:
Look up historical events and generate custom timelines.
Get information about a historical event:
Construct a timeline of events:
Find and compare historical countries, kingdoms and other territories.
Get information about a historical country or kingdom:
Compare multiple historical countries:
Explore dates, commanders, troops and casualties.
Find information about a military conflict:
Get information about a property of military conflicts:
Find current or historical political leaders by country and position.
Get information about a current political leader:
Get information about a past political leader:
Search and compare data about notable inventions and their creators.
Compare inventions:
Look up an invention property: