Conclusion

Well, that’s all there is to this little deconstruction that shows how you can use the Canvas APIs to figure out whether a font is available for your browser to use. Canvas is part of the HTML5 bucket of new things, so older IE browsers will not support it. If you care about the elderly (browsers), look into using the excellent explorercanvas library to bring the joys of Canvas to a larger audience unwilling or unable to upgrade to a modern browser.