When comparing Seal Report vs Jasper Reports, the Slant community recommends Jasper Reports for most people. In the question“What are the best open source reporting tools?” Jasper Reports is ranked 2nd while Seal Report is ranked 11th.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Multi database
Any database can be used, it's also possible to work without a database.
Pro HTML 5 charts
Supports ChartJS, NVD3 and Plotly libraries.
Pro Task scheduler
Pro Report designer
Designer with drag and drop support.
Pro Web Report Server
Requires IIS 7 or 8 with MVC4.
Pro LINQ Queries
Join different data sources.
Pro Has many more output formats than Nextreports
Pro Easy to learn
Pro Eclipse-based report designer is fairly easy to use
Jasperstudio report designer is easy enough to grok. It is full of features for designing your reports in a wysiwyg manner.
Pro Can be run as a service (server version) that allows deep links to individual reports or embedded with your web app as a library
You may or may not want a server version with its own learning curve and API. With Jasper you have the option of server vs library. With either one you can whip up reports and make them available in PDF, XML, HTML, CSV, XLS, RTF or TXT format. It's not very difficult to do that with JasperReports. And there are many examples out there to learn from.
Cons
Con Geared towards Java programmers
Extremely slow to load