diff --git a/Project.toml b/Project.toml
index e7d630e..6d77bea 100644
--- a/Project.toml
+++ b/Project.toml
@@ -17,3 +17,4 @@ Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 UnPack = "3a884ed6-31ef-47d7-9d2a-63182c4928ed"
 Unitful = "1986cc42-f94f-5a68-af5c-568840ba703d"
 UnitfulAstro = "6112ee07-acf9-5e0f-b108-d242c714bf9f"
+Zygote = "e88e6eb3-aa80-5325-afca-941959d7151f"
diff --git a/src/paramutils.jl b/src/paramutils.jl
index 8072e27..3c77de4 100644
--- a/src/paramutils.jl
+++ b/src/paramutils.jl
@@ -18,7 +18,7 @@ const Mpc_to_s = uconvert(u"s", u"Mpc" / c_0).val
 const year_to_s = 365.25 * 24 * 3600
 
 function mass_from_log10_mass(log10_M::Float64, eta::Float64)::Mass
-    M::Float64 = 0.0^log10_M * Msun_to_s
+    M::Float64 = 10.0^log10_M * Msun_to_s
     return Mass(M, eta)
 end
 
diff --git a/test/runtests.jl b/test/runtests.jl
index 8838603..5c8aa02 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -5,6 +5,7 @@ using LinearAlgebra
 using UnPack
 using NumericalIntegration
 using Statistics
+using Zygote
 
 
 e_from_τ_from_e(ecc::Float64)::Float64 = e_from_τ(τ_from_e(Eccentricity(ecc))).e
@@ -911,4 +912,15 @@ e_from_τ_from_e(ecc::Float64)::Float64 = e_from_τ(τ_from_e(Eccentricity(ecc))
         @test m1.m ≈ m2.m atol = 1e-6
     end
 
+    @testset "autodiff" begin
+        m = 1000.0
+        η = 0.2 
+        
+        @testset "parameters and conversions" begin
+            chirp_mass = (m, η) -> Mass(m, η).Mch
+            Mch = chirp_mass(m, η)
+            ∂Mch_∂m, ∂Mch_∂η = gradient(chirp_mass, m, η)
+            @test ∂Mch_∂m ≈ Mch / m && ∂Mch_∂η ≈ (3/5)*Mch/η
+        end
+    end
 end