Through the Federal Aviation Administration (FAA), the United States Government publishes VFR and IFR charts online for free. There are a number of free online sources for charts as well as a number of applications for mobile devices that also provide charts.
Pilots searching for enroute charts (e.g., Sectional Charts, TACs, or IFR enroute charts) can find them at www.skyvector.com.
In order to quickly locate an airport on the sectional chart, type its identifier into the text box in the upper left-hand corner of the screen. For example, type in 'KBOS', click the 'Go' button, and SkyVector will re-center the chart on Boston’s Logan International Airport. Surrounding the airport you will see the Boston Class B airspace as well as several nearby Class D airports.
To view additional charts, click one of the tabs located in the upper right-hand corner of the screen. For example, if SkyVector is displaying the Boston area, you can view the Lo-Altitude IFR Enroute Chart (L-33), the Hi-Altitude IFR Enroute Charts (H-10, H-11, and H-12), the Boston Terminal Area Chart, and others.
SkyVector also displays information and charts specific to a designated airport. To do this, click the 'Airports' link at the top of the screen and navigate to the desired airport. Once there, you will see the Airport Diagram near the top left of the page and the STARs, IAPs, and SIDs/DPs near the bottom. VFR pilots will only need to reference the provided Sectional Chart and Airport Diagram, while IFR pilots will need to reference IFR Enroute Charts as well as SIDs/DPs, STARs, and IAPs.
FAA chats are normally quite straightforward to read. Sometimes information is contained on one page; other times, it is spread across multiple pages. Be sure to always download multiple pages where they exist to ensure you receive all the information you need. For more information about how to read and use different types of charts, consider joining the community and working through some of the flights in our Pilot Ratings Program.
The following website are good resources for U.S. airport charts (e.g., Airport Diagrams, Instrument Approach Procedures, etc.):