You'll need: FontCreator (Windows and macOS), a font project that is heading toward thousands of glyphs, and — for Chinese, Japanese, or Korean work — a plan for which scripts and vertical metrics you need to cover.

Building a large or CJK font editor project is less about any single feature and more about staying organised across thousands of glyphs. This page is a hub: it points you to the dedicated tutorials for each part of the job, and explains the few things that are specific to working at scale. Treat it as a map rather than a manual — each linked page goes deeper on its own topic.

How big can a font get?

OpenType and TrueType fonts are limited to 65,535 glyphs by the format itself — glyph IDs are 16-bit, so the format simply cannot address more. That ceiling applies in every font editor and to every font file, not just FontCreator. For most Latin, Cyrillic, or Greek projects you will never come close. For full CJK coverage you may approach it, because a single comprehensive Chinese font can contain tens of thousands of Hanzi.

> Note: The glyph ceiling is a property of the font file format, not of FontCreator. If you need more than one font's worth of characters, the usual answer is to split coverage across more than one font file.

Unicode coverage vs glyph count vs export inclusion

These three numbers are related but not the same, and keeping them straight saves confusion on large fonts:

• Unicode coverage is which characters your font can be addressed by — the code points mapped in the font.
• Glyph count is how many actual outlines (glyphs) the font holds. One glyph can serve several code points, and many glyphs (components, alternates) carry no code point at all.
• Export inclusion is what actually ships in the finished font. FontCreator's Include in Exports setting (on the glyph's right-click menu in the font overview) controls whether a glyph is shipped — and lets you target all exports, none, or just the OpenType or web formats — so your working project can be larger than the exported file.

On a large font, design with all three in view: you might have 40,000 glyphs in the project, mapping 30,000 code points, and export a subset.

Adding custom Hanzi and PUA glyphs

CJK work often means adding characters that aren't in a starter template — scholarly or non-standard Hanzi, or glyphs placed in the Private Use Area (PUA). The mechanics of adding the empty cells and mapping them are the same as for any missing character.

See the Add Missing Characters & Codepoints tutorial for the step-by-step of inserting glyphs by Unicode code point and by name. That page covers the Insert Glyphs dialog, which supports insertion by Unicode value, so it applies directly to dropping in custom Hanzi or PUA slots.

> Tip: FontCreator is used in practice for exactly this kind of work — adding non-standard Chinese characters for specialist publishing is a documented real-world use of the font editor.

Navigating thousands of glyphs

A font with thousands of glyphs is unusable if you have to scroll to find anything. FontCreator's font overview is built around the categories and character panel, which gives quick access to glyphs, character subsets, and Unicode ranges — so you can jump straight to a script or block instead of scrolling.

Three tools work together for navigation at scale:

• Categories — filter the overview by Unicode range, script, or subset.
• Search / Find — jump to a glyph by name or code point.
• Tags and the No Tag filter — mark and re-find glyphs by production state.

For the tag-driven approach to sweeping a huge font to completion, see Glyph Tags & the No Tag Filter. The No Tag filter in particular is the practical way to make sure every one of thousands of glyphs has actually been reviewed.

Quality assurance at scale

The more glyphs you have, the more important it is to find problems automatically rather than by eye. FontCreator includes real-time font validation that flags outline and interpolation issues, and a validation pass that locates common glyph problems.

Rather than repeat the theory here, see the Test & Validate Your Font tutorial for how to run validation and interpret the results. On a large font, the workflow is: tag a region as "done", validate it, then move on — so validation and the tag sweep reinforce each other.

CJK vertical metrics

CJK fonts are frequently set vertically, which means they need vertical metrics. FontCreator supports vertical metrics for vertical writing. As the manual notes, vertical metrics are generally only useful in fonts intended for vertical writing, so in practice you'll add them in CJK fonts and leave them alone elsewhere.

This page deliberately does not re-explain the metrics theory. See Font Metrics – Vertical Line Spacing for how vertical line spacing values are calculated and set; apply that guidance to your CJK project rather than treating vertical metrics as a separate, CJK-only system.

> Watch out: Vertical metrics only matter if the font will be used in vertical writing mode. Adding them to a font that is only ever set horizontally adds complexity for no benefit.

Simplified vs Traditional coverage

Simplified and Traditional Chinese are different character sets with significant overlap but many distinct forms. Decide early which you are covering — Simplified only, Traditional only, or both — because that decision drives your glyph count, your Unicode coverage, and whether you are approaching the 65,535-glyph ceiling. There is no automatic converter from one to the other: coverage is simply a matter of which glyphs you choose to include in the project.

Export and file size

CJK and other large fonts produce large files, simply because they contain so many outlines. A few things to keep in mind on export:

• FontCreator supports OpenType, TrueType, and the web formats WOFF and WOFF2, and export performance for large fonts has been improved over successive releases.
• Use Include in Exports to keep the shipped file to the coverage you actually need — glyphs flagged out of an export stay in your project but never reach that font file.

> Watch out: WOFF2 for very large CJK fonts. WOFF2 compresses aggressively, which is excellent for the web, but a full CJK web font can still be megabytes in size — large enough that downloading the whole thing on every page load is impractical. For CJK on the web, plan for subsetting or unicode-range slicing rather than shipping one enormous WOFF2. (Subsetting is a general web-font practice you apply downstream of FontCreator, not a FontCreator export switch.)

Performance with large fonts

Editing tens of thousands of glyphs is demanding, and FontCreator has had repeated work to improve speed while editing large fonts. In day-to-day use the practical levers are the same as the navigation tools above: filter with categories, jump with search, and use tags so you are only ever looking at the subset you care about — rather than asking the editor to render the whole font at once.

> Tip: If a large project feels sluggish, work inside a filtered category or a tag subcategory instead of the full overview. You get the same glyphs with far less for the editor to draw.

Frequently asked questions

What is the maximum number of glyphs in a font? The OpenType/TrueType format limit is 65,535 glyphs, because glyph IDs are 16-bit. It is a property of the font file format, so it applies in every font editor and to every font.

Can FontCreator handle a full Chinese font? Yes — FontCreator is used in practice to build and extend Chinese fonts, including adding non-standard characters. Expect large file sizes and plan navigation around categories, search, and tags.

Does FontCreator support vertical writing for CJK? Yes, it supports vertical metrics, which are intended for fonts used in vertical writing. See Font Metrics – Vertical Line Spacing for the details.

Should I export a large CJK font as WOFF2 for the web? WOFF2 is supported and compresses well, but a complete CJK font may still be too large to ship in one file. For the web, plan to subset rather than deliver full coverage in a single download.

How do I keep track of which glyphs are finished in a big font? Use glyph tags and the No Tag filter. See Glyph Tags & the No Tag Filter.

What to read next

• Glyph Tags & the No Tag Filter — the tag-driven sweep that makes large and CJK fonts manageable.
• Add Missing Characters & Codepoints — inserting custom Hanzi and PUA glyphs by code point and by name.
• Test & Validate Your Font — quality assurance once a region is complete.
• Font Metrics – Vertical Line Spacing — the vertical metrics theory CJK fonts rely on.