xUnit.net vs Testing Library

Feature checklists rarely decide anything. What decides it is the pricing metric, who has to write the tests, and which limitation you can live with.

xUnit.netTesting Library

Entry price

Free and open source

Open source

Free and open source

Open source

What drives the bill

The metric that actually scales your invoice.

Free and open source. You pay in engineering time and CI minutes.

Free tier

Everything, self-hosted

Open source

Apache-2.0

MIT

Self-hostable

No-code authoring

Languages

JavaScriptTypeScript

Platforms

WebAPIDesktop

Web

Fits teams

StartupScale-up / mid-marketEnterprise

Solo / side projectStartupScale-up / mid-marketEnterprise

Adoption

Category standard

.NET Foundation · since 2007

Category standard

OSS community · since 2018

Strengths

Per-test instance isolation eliminates a whole class of shared-state bugs by design.
Idiomatic modern C# — no attribute soup.
The default in current .NET project templates.

Tests survive refactors because they assert on user-visible output, not internals.
Accessible-role queries push teams towards accessible markup as a side effect.
One idiom across every major front-end framework.

Limitations

Deliberately makes implementation-detail testing hard, which frustrates teams used to shallow rendering.
Async utilities and act() warnings are a common source of confusion.
Needs a runner and a DOM environment alongside it.

Best for

New .NET projects.

Any front-end team writing component tests, regardless of framework.

Pricing last reviewed August 2026 and is indicative only — confirm on each vendor’s own page.