# \[ANN\] UnitfulSystems.jl unifies Unitful.jl + UnitSystems.jl
**URL:** https://discourse.julialang.org/t/ann-unitfulsystems-jl-unifies-unitful-jl-unitsystems-jl/51997
**Category:** Package Announcements
**Tags:** unitful
**Created:** [December 17, 2020, 5:14pm UTC](https://discourse.julialang.org/t/ann-unitfulsystems-jl-unifies-unitful-jl-unitsystems-jl/51997 "2020-12-17T17:14:27Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@tk3369](https://discourse.julialang.org/u/tk3369)
#### Post date: [December 17, 2020, 5:14pm UTC](https://discourse.julialang.org/t/ann-unitfulsystems-jl-unifies-unitful-jl-unitsystems-jl/51997/1 "2020-12-17T17:14:27Z")
Hi,
I’m happy to announce a new package on behalf of Michael. While he is banned from the Julia community (long story that I am not knowledgeable enough to comment about), I applaud his continued contribution to open-source. He’s still active on Reddit and GitHub should you need to contact him or talk to him about his work.
> **[GitHub - chakravala/UnitSystems.jl: Physical unit systems (Metric, English,...](https://github.com/chakravala/UnitSystems.jl)**
>
> Physical unit systems (Metric, English, Natural, etc...) - GitHub - chakravala/UnitSystems.jl: Physical unit systems (Metric, English, Natural, etc...)
In his own words:
> UnitSystems supports many more UnitSystem types, such as EMU, ESU, Gauss, and LorentzHeaviside CGS electromagnetic unit conversions, which Unitful does not support. It also suppports every type of Natural unit possible, and conversions from any of these to any other system. UnitSystems also loads much faster than Unitful and compiles much faster, while also able to give you 42 physical constants in any choice of UnitSystem, unlike Unitful. It does all this while loading about 5-10x faster, which is useful for running scripts.
>
> UnitSystems could be used as a more accurate source of unit conversion factors, since I found that the Unitful conversion factors aren’t as accurate. I could see Unitful someday depending on UnitSystems as a source for those conversions factors, but don’t really care if it does that or not.
>
> The documentation is at [Standard Units · Geophysics.jl](https://geophysics.crucialflow.com/dev/units)
>
> Not even Wikipedia or the NIST/CODATA resources have as much / complete unit information available as I make available in my resource.
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### Author:  [@roble](https://discourse.julialang.org/u/roble)
#### Post date: [December 18, 2020, 12:13am UTC](https://discourse.julialang.org/t/ann-unitfulsystems-jl-unifies-unitful-jl-unitsystems-jl/51997/2 "2020-12-18T00:13:05Z")
I think this is a quality package 👍
Many thanks for sharing this
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### Author:  [@rafael.guerra](https://discourse.julialang.org/u/rafael.guerra)
#### Post date: [December 18, 2020, 9:28am UTC](https://discourse.julialang.org/t/ann-unitfulsystems-jl-unifies-unitful-jl-unitsystems-jl/51997/3 "2020-12-18T09:28:56Z")
The author of the package has started a [post](https://www.reddit.com/r/Julia/comments/k6jnpq/is_unitsystemsjl_the_most_complete_resource_for/) in reddit titled “_Is UnitSystems.jl the most complete resource for physics constants?_”…