How to Subset Fonts Online
Step-by-step instructions to subset embedded fonts to reduce pdf file size with ZiaSign.
Why this workflow matters
ZiaSign's font subsetter removes unused character glyphs from embedded fonts, reducing PDF file size. If your PDF uses Arial but only 50 characters, the other 65,000+ glyphs are removed. Significant savings for font-heavy documents.
Step by step
Subset Fonts is one of the fastest ways to subset embedded fonts to reduce pdf file size. Pro access gives you the full workflow.
- 1
Upload your PDF
- 2
Fonts are analyzed for unused glyphs
- 3
Click 'Subset Fonts'
- 4
Download the optimized PDF
Frequently asked questions
What is font subsetting?
Subsetting keeps only the characters used in the document, removing unused glyphs to save space.
How much space does subsetting save?
A typical font has 65,000+ glyphs. If your document uses only 200 characters, subsetting removes 99% of font data.
Will the document look different after subsetting?
No. All visible text renders identically. Only unused character data is removed from the embedded font files.
Can I add text to a subsetted PDF later?
You can add text, but only characters present in the subset will render correctly. For full font availability, use the original un-subsetted version.
More specific workflows for this tool
Related guides
How to Extract Images Online
Step-by-step instructions to extract all embedded images from a pdf with ZiaSign.
Read guideHow to Extract Text Online
Step-by-step instructions to extract text content from pdf pages with ZiaSign.
Read guideHow to Optimize PDF Online
Step-by-step instructions to optimize pdf for fast web viewing (linearize) with ZiaSign.
Read guideReady to run the actual workflow?
You have the steps. Open the tool, process the file, and then move into the next recommendation if the document still needs cleanup, protection, or conversion.