kernlab is an R package for kernel-based machine learning methods. It provides a framework for creating and using kernel-based algorithms, including support vector machines (SVM), relevance vector machines (RVM), Gaussian processes, kernel PCA, kernel CCA, kernel feature analysis, online kernel methods, and spectral clustering. The package uses R's S4 object model and includes a quadratic programming solver and an incomplete Cholesky decomposition method. It supports various kernel functions, such as linear, Gaussian, polynomial, and hyperbolic tangent kernels. kernlab allows users to define their own kernels and provides utility functions for computing kernel matrices and performing kernel-based learning tasks. The package includes data sets for demonstration and supports a wide range of kernel-based algorithms, including SVM, RVM, Gaussian processes, ranking, and spectral clustering. It also includes methods for online learning and kernel-based feature analysis. kernlab is extensible and provides a unified framework for using and creating kernel-based algorithms in R.kernlab is an R package for kernel-based machine learning methods. It provides a framework for creating and using kernel-based algorithms, including support vector machines (SVM), relevance vector machines (RVM), Gaussian processes, kernel PCA, kernel CCA, kernel feature analysis, online kernel methods, and spectral clustering. The package uses R's S4 object model and includes a quadratic programming solver and an incomplete Cholesky decomposition method. It supports various kernel functions, such as linear, Gaussian, polynomial, and hyperbolic tangent kernels. kernlab allows users to define their own kernels and provides utility functions for computing kernel matrices and performing kernel-based learning tasks. The package includes data sets for demonstration and supports a wide range of kernel-based algorithms, including SVM, RVM, Gaussian processes, ranking, and spectral clustering. It also includes methods for online learning and kernel-based feature analysis. kernlab is extensible and provides a unified framework for using and creating kernel-based algorithms in R.