# \[ANN\] UnitfulGauss.jl, Gaussian EM units with proper gaussian physical dimensions

**URL:** <https://discourse.julialang.org/t/ann-unitfulgauss-jl-gaussian-em-units-with-proper-gaussian-physical-dimensions/138162>\
**Category:** Package Announcements\
**Tags:** unitful\
**Created:** [July 13, 2026, 5:43pm UTC](https://discourse.julialang.org/t/ann-unitfulgauss-jl-gaussian-em-units-with-proper-gaussian-physical-dimensions/138162 "2026-07-13T17:43:49Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![Gregstrq](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gregstrq/32/20620_2.png) [@Gregstrq](https://discourse.julialang.org/u/Gregstrq)\
**Post date:** [July 13, 2026, 5:43pm UTC](https://discourse.julialang.org/t/ann-unitfulgauss-jl-gaussian-em-units-with-proper-gaussian-physical-dimensions/138162/1 "2026-07-13T17:43:49Z")

</div>

I would like to announce [UnitfulGauss.jl](https://github.com/Gregstrq/UnitfulGauss.jl) — a small extension package for [Unitful.jl](https://github.com/JuliaPhysics/Unitful.jl) that defines Gaussian electromagnetic units with the proper Gaussian physical dimensions.

Although [Unitful.jl](https://github.com/JuliaPhysics/Unitful.jl) defines the Gaussian units, they have the physical dimensions corresponding to the SI unit system. If you would try to stick those into the equations expressed in the Gaussian unit system, you’d get nonsensical results.

Not to clash with the units defined by [Unitful.jl](https://github.com/JuliaPhysics/Unitful.jl), [UnitfulGauss.jl](https://github.com/Gregstrq/UnitfulGauss.jl) uses the same symbols for the electromagnetic units but appends superscript g at the end. For example, the Coulomb unit of charge with gaussian physical dimension `sqrt(𝐌*𝐋^3)/𝐓` is accessed as `UnitfulGauss.Cᵍ`.

The package exports the string macro `@ug_str`, which functions identically to the `@u_str` defined by [Unitful.jl](https://github.com/JuliaPhysics/Unitful.jl), but chooses the proper gaussian versions for the electromagnetic units under the hood

```julia
using UnitfulGauss

using UnitfulGauss

ug"C" === UnitfulGauss.Cᵍ 
ug"Gauss" === UnitfulGauss.Gaussᵍ
ug"V/cm" === UnitfulGauss.Vᵍ/UnitfulGauss.Unitful.cm

```

In addition to that, the package also exports functions `to_gauss` and `to_si`, which translate the units and quantities to the gaussian unit system and back. This is useful if you want to translate the physical constants, for example.

```julia
using UnitfulGauss, PhysicalConstants

import PhysicalConstants.CODATA2022: ε_0

ε₀ᵍ = uconvert(UnitfulGauss.NoUnits, ε_0 |> float |> to_gauss)

4π*ε₀ᵍ ≈ 1.0

```

As expected, in the Gaussian system, the vacuum permeability is a dimensionless constant equal to `1/4π`.

Finally, you can use the package without explicitly importing [Unitful.jl](https://github.com/JuliaPhysics/Unitful.jl). It reexports Unitful.jl, imports derived dimensions and even provides the true Gaussian versions of the physical constants defined in Unitful.jl.