FontPlop is a browser-based font viewer and tester that supports TTF, OTF, WOFF, and WOFF2 font files. The tool is designed for inspecting fonts the way a type designer would, displaying every glyph in a font with its Unicode value, width, and other metrics. Users can drop a font file onto the page or select it with a file button, and the viewer will render the complete character set, including any empty boxes or missing shapes that may indicate problems. The viewer includes a text tester that lets users type a headline or paste a paragraph and read it at small and large sizes in a waterfall format. Users can toggle OpenType features such as ligatures, figures, and stylistic sets, then copy the resulting CSS. The tool also displays the names and licence stored in the file, the OpenType features it contains, its variable axes, and the languages its character set covers. A Metrics & checks tab runs automated tests for common font issues, including missing characters, clipped vertical metrics, inconsistent names, and restricted embedding, with explanations of what each result means. FontPlop is intended for type designers, web developers, and anyone who needs to verify a font before shipping or using it in a project. Because all processing happens locally in the browser using open-source libraries, font files are never uploaded to a server, which makes it safe to check unreleased or licensed fonts. The viewer requires JavaScript to function. Font collections (.ttc), Mac suitcases (.dfont), and ZIP downloads are not supported and must be unpacked or converted first. The page also includes related font tools, such as a webfont generator that converts TTF or OTF files to WOFF2 and WOFF with @font-face CSS, a font comparison feature for overlaying two fonts and comparing metrics, an OpenType features reference with live previews, and a kerning game that tests letter spacing skills. Additional generators and text style tools are available for creating fancy fonts, images, and social media text.