diff --git a/test/benchmarks.jl b/test/benchmarks.jl
new file mode 100644
index 00000000..6fb0f557
--- /dev/null
+++ b/test/benchmarks.jl
@@ -0,0 +1,76 @@
+using Unitful
+using BenchmarkTools
+using Base.Test
+using DataFrames
+
+function benchmark()
+    suite = BenchmarkGroup(["Unitful"])
+    bterms = (3u"kg", 3.5u"kg", 2u"m^-1")
+    for a in (2u"m", 2.1u"m"), b in bterms, op in (:*, :/)
+        benchmark!(suite, :($op($a, $b)))
+    end
+    for a in (2u"m", 2.1u"m"), b in (3u"m", 3.5u"m"), op in (:+, :-)
+        benchmark!(suite, :($op($a, $b)))
+    end
+
+    performance_summary(suite)
+end
+
+function judge_unit_benchmark(units::Expr, nounits::Expr; kwargs...)
+    op = units.args[1]
+    a = eval(units.args[2])
+    b = eval(units.args[3])
+    bench_units = @benchmarkable $op($a, $b)
+    bench_nounits = @benchmarkable $nounits
+    tune!(bench_units)
+    tune!(bench_nounits)
+    judge(
+        median(run(bench_units; kwargs...)),
+        median(run(bench_nounits; kwargs...))
+    )
+end
+
+function judge_unit_benchmark(units::Expr; kwargs...)
+    op = units.args[1]
+    a = ustrip(eval(units.args[2]))
+    b = ustrip(eval(units.args[3]))
+    judge_unit_benchmark(units, :($op($a, $b)); kwargs...)
+end
+
+function test_benchmark(unit::Expr...; kwargs...)
+    j = judge_unit_benchmark(unit...; kwargs...)
+    j.time == :invariant && j.memory == :invariant
+end
+
+@testset "Benchmarks" begin
+    as, ops, bs = (2u"m", 2.1u"m"), (:*, :/), (3u"kg", 3.5u"kg")
+    @testset "$a $op $b" for a = as, b = bs, op = ops
+        @test test_benchmark(:($op($a, $b)), time_tolerance=0.01)
+    end
+
+    @testset "unit to unitless" begin
+        @test test_benchmark(:((1u"m") / (2u"m")), time_tolerance=0.01)
+        @test test_benchmark(:(1u"m" * 2u"m^-1"), time_tolerance=0.01)
+        @test test_benchmark(:(1u"m" / 2u"km"), time_tolerance=0.01)
+    end
+
+
+    a  = 1//2 * u"m"
+    bs = (1u"kg", 2//3 * u"kg")
+    @testset "rational numbers: $a $op $b" for b = bs, op in (://, :*)
+        @test_broken test_benchmark(:($op($a, $b)))
+    end
+
+    @testset "summations" begin
+        @test test_benchmark(:(1u"m" + 2u"m"), time_tolerance=0.01)
+        @test_broken test_benchmark(:(1u"km" + 2u"m"), time_tolerance=0.01)
+    end
+
+    @testset "Arrays" begin
+        as, ops, bs = ([2, 1]u"m", [2.1, 3.1]u"m"), (:.*, :./, :.+, :.-),
+                      (3u"kg", [3, 2]u"kg")
+        @testset "$a $op $b" for a=as, b=bs, op=ops
+            @test_broken test_benchmark(:($op($a, $b)), time_tolerance=0.01)
+        end
+    end
+end