How to merge two fonts

You can merge two fonts into one file in Font Studio's Compare & Compose workspace: load a base font and a donor font, compare them character by character, choose what to take from each, and build the result — entirely on your device. Composing is free with up to two sources.

Typical jobs: a base font missing "é", "ñ" and "€" that pulls them from a donor; a text face and a symbol set becoming one file; a color-emoji source donating artwork into a working font.

Before you start

• The fonts should share a style. Merging works technically even when the designs clash; it just looks bad. Compare them first with Font comparison.
• Same units-per-em avoids a rescale. Different UPM values work — Compose rescales and warns you — but identical UPM is cleaner.
• Keep both originals, and make sure the licenses permit a merged derivative (licensing basics).

Step 1 — Add the sources

Open a font in the workspace — it becomes the base, the one that wins conflicts by default — and pick Compare & Compose from the ⋮ Command Center. Add the donor font as the second source. Added them in the wrong order? Make this the base fixes it.

Step 2 — Compare

The compare view shows every character across all sources with per-source presence — including "not in this font" rows, which is the fastest way to spot a coverage gap. Search understands code points (U+0041, 0x41) and block names ("Currency Symbols").

Step 3 — Compose with a scope and a policy

Two decisions define the build:

• Scope — what to compose: Merge all (take everything), Add missing glyphs (the donor only fills gaps; nothing in the base is touched), or Selected glyphs (Pro — only the characters you pick)
• Conflict policy — who wins a shared character: Keep base, Use incoming, or Review each (Pro)

The live summary shows real numbers computed from the fonts' actual character maps — per source: characters that will be added, will be replaced, or will be skipped. Change the scope or policy and the numbers update; nothing is guessed.

Step 4 — Build and read the warnings

Tap Build Result. If anything cannot carry over, the pre-build warnings say so explicitly — layout tables, a rescaled UPM, unsupported color formats. Read them: they are the honest cost of the merge.

Then Apply to Project to keep editing, or Save as a Font File — the output is saved as a TTF with a _composed name.

After the merge

• Spot-check the characters that came from the donor in the Font Inspector or the workspace preview.
• Run Font Health if anything renders oddly — merges of messy sources inherit their quirks, and the build warnings told you which.

The scalpel alternative

For one or two characters, a full merge is overkill. Glyph Replacement (Pro) swaps exactly the code points you name — the donor's glyph overwrites just those characters, everything else untouched. The decision table is in Adding glyphs.

What to try next

• Shrinking the merged result? How to reduce font file size
• A source font that misbehaves? How to repair a corrupted font