diff --git a/base/rational.jl b/base/rational.jl
index 8c5244ea4bad3..707b740fb2048 100644
--- a/base/rational.jl
+++ b/base/rational.jl
@@ -443,7 +443,7 @@ fma(x::Rational, y::Rational, z::Rational) = x*y+z
 
 function ==(x::AbstractFloat, q::Rational)
     if isfinite(x)
-        (count_ones(q.den) == 1) & (x*q.den == q.num)
+        (count_ones(q.den) == 1) & (ldexp(x, top_set_bit(q.den-1)) == q.num)
     else
         x == q.num/q.den
     end
diff --git a/test/rational.jl b/test/rational.jl
index fe707cb7d3521..b07842e759f99 100644
--- a/test/rational.jl
+++ b/test/rational.jl
@@ -837,3 +837,8 @@ end
         @test_throws OverflowError numerator(Int8(1)//Int8(31) + Int8(8)im//Int8(3))
     end
 end
+
+@testset "Float16 comparison" begin
+    @test Float16(6.0e-8) == big(1//16777216) == 1//16777216
+    @test Float16(6.0e-8) == 1//16777216
+end