Benchmarks

These measurements describe the current implementations, not their final performance potential; several known optimization opportunities have not yet been implemented.

These results compare complete public JavaScript layout transactions in Node.js. Every scenario runs through @taffyjs/node, @taffyjs/wasm, @taffyjs/yoga, @taffyjs/yoga-wasm, and yoga-layout. The two public API shapes use explicit implementations of the same semantic workload, including their real tree construction, conversion, layout, output-read, callback, and lifecycle costs.

Each scenario asks a different question and stands on its own. Relative throughput uses yoga-layout as the 1.00× reference. Results from different scenarios are not combined into an overall score or winner.

The publication profile uses 1 isolated round per target. Each round must stay at or below 30% relative margin of error.

Small nested UI: 50 nodes

What does a complete 50-node nested layout transaction cost?

A deterministic near-balanced hierarchy alternates row and column Flexbox containers. It represents nested application UI while keeping the topology identical for every package and API.

Timed transaction

Create the public tree, apply styles, attach every child, calculate layout, read left/top/width/height for every node, and release resources when the API requires it.

Scale

node count

50

leaf count

25

depth

7

maximum branching factor

2

viewport width

1,200

viewport height

800

Small nested UI: 50 nodes throughput and latency by package

Package	API	Runtime	ops/s	Median	vs yoga-layout yoga-layout = 1.00×
@taffyjs/node	TaffyTree	Native Node-API	1,256.39	0.781 ms	0.524×
@taffyjs/wasm	TaffyTree	WASI Wasm	194.17	5.043 ms	0.081×
@taffyjs/yoga	Yoga Node	Native Taffy	151.28	6.329 ms	0.063×
@taffyjs/yoga-wasm	Yoga Node	WASI Taffy	22.43	44.207 ms	0.009×
yoga-layout	Yoga Node	Yoga Wasm	2,399.91	0.401 ms	1.00×

Nested UI: 500 nodes

What does a complete 500-node nested layout transaction cost?

A deterministic near-balanced hierarchy alternates row and column Flexbox containers. It represents nested application UI while keeping the topology identical for every package and API.

Timed transaction

Create the public tree, apply styles, attach every child, calculate layout, read left/top/width/height for every node, and release resources when the API requires it.

Scale

node count

500

leaf count

250

depth

10

maximum branching factor

2

viewport width

1,200

viewport height

800

Nested UI: 500 nodes throughput and latency by package

Package	API	Runtime	ops/s	Median	vs yoga-layout yoga-layout = 1.00×
@taffyjs/node	TaffyTree	Native Node-API	30.77	31.895 ms	0.368×
@taffyjs/wasm	TaffyTree	WASI Wasm	12.61	77.552 ms	0.151×
@taffyjs/yoga	Yoga Node	Native Taffy	11.46	85.727 ms	0.137×
@taffyjs/yoga-wasm	Yoga Node	WASI Taffy	1.95	513.400 ms	0.023×
yoga-layout	Yoga Node	Yoga Wasm	83.57	11.923 ms	1.00×

Wide wrapping collection: 500 items

What does a complete layout transaction cost for one broad wrapping collection?

A two-level Flexbox collection exercises broad child lists, wrapping, repeated style conversion, child attachment, layout reads, and resource release without random fixture generation.

Timed transaction

Create the public root and 500 items, apply styles, attach every item, calculate layout, read left/top/width/height for every node, and release resources when the API requires it.

Scale

item count

500

node count

501

depth

2

viewport width

1,200

Wide wrapping collection: 500 items throughput and latency by package

Package	API	Runtime	ops/s	Median	vs yoga-layout yoga-layout = 1.00×
@taffyjs/node	TaffyTree	Native Node-API	222.77	4.310 ms	0.357×
@taffyjs/wasm	TaffyTree	WASI Wasm	30.78	31.079 ms	0.049×
@taffyjs/yoga	Yoga Node	Native Taffy	19.94	49.487 ms	0.032×
@taffyjs/yoga-wasm	Yoga Node	WASI Taffy	2.60	380.510 ms	0.004×
yoga-layout	Yoga Node	Yoga Wasm	623.17	1.534 ms	1.00×

Coding-agent chat: initial layout

What does it cost to build, measure, lay out, read, and release a modeled coding-agent screen?

A fixed desktop chat fixture contains a session sidebar, measured labels, a message transcript, and a composer. Text callbacks use the same intrinsic-size function and constraints for both public APIs.

Timed transaction

Create the public tree from fixed fixture data, calculate with public text-measure callbacks, read left/top/width/height for every node, and release resources when the API requires it.

Scale

node count

285

measured node count

51

session count

18

message count

32

viewport width

1,280

viewport height

800

Coding-agent chat: initial layout throughput and latency by package

Package	API	Runtime	ops/s	Median	vs yoga-layout yoga-layout = 1.00×
@taffyjs/node	TaffyTree	Native Node-API	21.32	46.212 ms	0.024×
@taffyjs/wasm	TaffyTree	WASI Wasm	2.73	363.489 ms	0.003×
@taffyjs/yoga	Yoga Node	Native Taffy	12.18	81.655 ms	0.014×
@taffyjs/yoga-wasm	Yoga Node	WASI Taffy	1.61	617.934 ms	0.002×
yoga-layout	Yoga Node	Yoga Wasm	901.66	1.043 ms	1.00×

Coding-agent chat: viewport resize

What does it cost to relayout an existing measured application tree after a resize?

The same coding-agent fixture is created and initially laid out before timing. Each transaction alternates between two fixed viewport sizes, recomputes measured layout, and reads every result.

Timed transaction

Update the persistent root size through the public API, calculate layout with public text-measure callbacks, then read left/top/width/height for every node. Setup and final release are outside timing.

Scale

node count

285

measured node count

51

session count

18

message count

32

initial viewport width

1,280

initial viewport height

800

resized viewport width

1,024

resized viewport height

768

Coding-agent chat: viewport resize throughput and latency by package

Package	API	Runtime	ops/s	Median	vs yoga-layout yoga-layout = 1.00×
@taffyjs/node	TaffyTree	Native Node-API	50.77	19.081 ms	0.013×
@taffyjs/wasm	TaffyTree	WASI Wasm	6.33	158.681 ms	0.002×
@taffyjs/yoga	Yoga Node	Native Taffy	23.47	41.570 ms	0.006×
@taffyjs/yoga-wasm	Yoga Node	WASI Taffy	3.43	290.868 ms	0.001×
yoga-layout	Yoga Node	Yoga Wasm	3,980.17	0.249 ms	1.00×

Run details

Node.js

v24.19.0

Operating system

linux 6.18.25-x64v3-xanmod1 (x64)

CPU

13th Gen Intel(R) Core(TM) i5-13500H

Commit

1cbbd1595f536e665f67e0e9757c9ca27fcf8c46