Sort children of <defs> (`sortDefsChildren`)

Sorts children inside <defs> for stable output and improved compressibility.

What Sort children of <defs> does in SVGO

SVGO applies sortDefsChildren as part of its plugin pipeline. On SVGOMG.net the toggle is labeled Sort children of <defs> (enabled by default). Optimization runs entirely in your browser — files are not uploaded to a server.

Use SVGOMG.net with Show original to compare before and after. If output looks wrong, disable this plugin first, then re-enable related transforms one at a time.

When to enable

SVGs with large symbol libraries or sprite sheets.

When to disable

When defs order matters for human editing workflows only.

Watch out for

Does not change rendering.

Try it

Open SVGOMG.net and load your SVG (file, paste, or demo).
Find Sort children of <defs> in the Features panel (sortDefsChildren).
Toggle the plugin and compare the preview; download when satisfied.

Part of: IDs, defs, and references

This plugin is covered in the IDs, defs, and references topic guide along with related transforms.

SVGO Plugin Guide

Browse the SVGO Plugin Guide or read the full SVG optimization walkthrough.