FontCreator is the world's most popular font editor and comes with a complete feature set that makes it the tool of choice for professionals. Its intuitive interface is straightforward enough for users at any expertise level.
Here is a list that shows the most important features and benefits. For more detailed feature descriptions, do consult the manual and the forum, which are both available through the support page.
Create and edit TrueType and OpenType fonts
Full support for variable fonts (quadratic bezier curves)
Create and edit Web Open Font Format (WOFF and WOFF2) fonts with superior compression
Create and edit scalable color fonts (supporting COLR, CPAL, and SVG tables)
Supports the UFO and DesignSpace formats
Import and export .glyphs files
Subsetting glyphs (e.g. exclude glyphs from exporting)
OpenType features are preserved upon opening a font
Visually edit OpenType layout features
Supports all basic languages, including but not limited to English, German, French, Dutch, Italian, Danish, Swedish, Norwegian, Spanish, Portuguese, Basque, Estonian, Faeroese, Frisian, Irish, Galician, Hungarian, Icelandic, Albanian, and Esperanto
Supports complex script fonts covering Arabic, Syriac, Hebrew, and more
Advanced OpenType feature generator
OpenType feature code can also be edited
Edit, import, and export VOLT feature code
Edit, import, and export AFDKO feature code (aka .fea syntax)
Powerfull OpenType layout feature proofing and debugging tool
FontCreator supports both quadratic- and cubic-based contours
Optimize contours to reduce the number of nodes
Fix character mappings
Unicode variation sequences
Last resort fonts
Correct fonts that display incorrectly
Find and replace glyph names
Hybrid glyph outlines
Glyph tagging
Open and save fonts in Unified Font Object (UFO) format
Convert OpenType fonts to TrueType fonts
Convert TrueType fonts to OpenType fonts
Generate, modify, import, export, and clean up kerning pairs
Add or correct over three thousand composite glyphs
Transform individual glyphs or an entire font (e.g. to make a bold version)
Extract TrueType fonts from TrueType Collections
Unicode support (including the private use area and supplementary planes)
View unknown font tables
All popular encodings and code pages supported (ANSI, ASCII, Unicode, Symbol, Big5, PRC, Wansung, etc)
Vertical metrics; mostly useful with fonts that are used for vertical writing, e.g. Chinese, Japanese, and Korean fonts