diff --git a/fuzz/.gitignore b/fuzz/.gitignore
new file mode 100644
index 0000000..a092511
--- /dev/null
+++ b/fuzz/.gitignore
@@ -0,0 +1,3 @@
+target
+corpus
+artifacts
diff --git a/fuzz/Cargo.toml b/fuzz/Cargo.toml
new file mode 100644
index 0000000..b009efc
--- /dev/null
+++ b/fuzz/Cargo.toml
@@ -0,0 +1,25 @@
+[package]
+name = "floatconv-fuzz"
+version = "0.0.0"
+authors = ["Automatically generated"]
+publish = false
+edition = "2018"
+
+[package.metadata]
+cargo-fuzz = true
+
+[dependencies]
+libfuzzer-sys = "0.4"
+
+[dependencies.floatconv]
+path = ".."
+
+# Prevent this from interfering with workspaces
+[workspace]
+members = ["."]
+
+[[bin]]
+name = "hard_u128_to_f64_round"
+path = "fuzz_targets/hard_u128_to_f64_round.rs"
+test = false
+doc = false
diff --git a/fuzz/fuzz_targets/hard_u128_to_f64_round.rs b/fuzz/fuzz_targets/hard_u128_to_f64_round.rs
new file mode 100644
index 0000000..c356f07
--- /dev/null
+++ b/fuzz/fuzz_targets/hard_u128_to_f64_round.rs
@@ -0,0 +1,6 @@
+#![no_main]
+use libfuzzer_sys::fuzz_target;
+
+fuzz_target!(|data: u128| {
+    assert_eq!(floatconv::fast::u128_to_f64_round(data), data as f64);
+});