diff --git a/Cargo.toml b/Cargo.toml
index 7970c8e..108d39b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,10 +13,12 @@ edition = '2021'
 
 [dependencies]
 serde = "1.0"
-bnum = {version = "0.5.0", features = ["num-traits"]}
+bnum = {version = "0.5.0", features = ["numtraits"]}
 num-traits = "0.2"
+num-integer = "0.1"
 
 [dev-dependencies]
 serde_json = "1.0"
 serde_derive = "1.0"
 lazy_static = "1.4"
+rand = "0"
\ No newline at end of file
diff --git a/src/int256.rs b/src/int256.rs
index 030e0ae..9fa59ff 100644
--- a/src/int256.rs
+++ b/src/int256.rs
@@ -1,5 +1,6 @@
 use bnum::types::I256;
 use bnum::BInt;
+use num_integer::Roots;
 use num_traits::{
     Bounded, CheckedAdd, CheckedDiv, CheckedMul, CheckedSub, FromPrimitive, Num, One, Pow, Signed,
     ToPrimitive, Zero,
@@ -57,7 +58,7 @@ impl Int256 {
 
     /// Square root
     pub fn sqrt(&self) -> Uint256 {
-        self.0.ilog(self.0).into()
+        Uint256(self.0.sqrt().unsigned_abs())
     }
 
     /// Checked conversion to Uint256
@@ -321,7 +322,7 @@ macro_rules! forward_checked_op {
         impl $trait_ for $type_ {
             fn $method(&self, $type_(b): &$type_) -> Option<$type_> {
                 let $type_(a) = self;
-                let value = a.$method(*b);
+                let value = a.$method(b);
                 match value {
                     Some(value) => Some(Int256(value)),
                     None => None,
@@ -381,7 +382,7 @@ fn check_from_str_radix_overflow_underflow() {
 #[test]
 fn test_to_primitive_64() {
     use num_traits::ToPrimitive;
-    let u32_max: u64 = std::u32::MAX.into();
+    let u32_max: u64 = u32::MAX.into();
     let mut i = 0u64;
     while i < 100_000 {
         let i_int256: Int256 = i.into();
@@ -410,7 +411,7 @@ fn test_to_primitive_64() {
 /// Check the ToPrimitive impl for +-[0, 100k] and +-[2^64-100, ~2^64+100k]
 #[test]
 fn test_to_primitive_128() {
-    let u64_max: u128 = std::u64::MAX.into();
+    let u64_max: u128 = u64::MAX.into();
     use num_traits::ToPrimitive;
     let mut i = 0u128;
     while i < 100_000 {
@@ -444,9 +445,9 @@ fn test_to_from_bytes() {
     let n1 = Int256::from(-1i8);
     let z = Int256::zero();
     let p1 = Int256::from(1i8);
-    let p_u64max = Int256::from(std::u64::MAX);
+    let p_u64max = Int256::from(u64::MAX);
     let n_u64max = p_u64max.neg();
-    let p_u128max = Int256::from(std::u128::MAX);
+    let p_u128max = Int256::from(u128::MAX);
     let n_u128max = p_u128max.neg();
     let int256_max = Int256::max_value();
     let int256_min = Int256::min_value();
@@ -459,3 +460,15 @@ fn test_to_from_bytes() {
         assert_eq!(tc, to_from_le(tc));
     }
 }
+
+#[test]
+fn test_sqrt() {
+    use rand::prelude::*;
+
+    for _ in 1..100000 {
+        let r: i128 = random();
+        let n = Int256::from(r.abs());
+        let sqrt = (n.mul(n)).sqrt();
+        assert!(sqrt == n.to_uint256().unwrap());
+    }
+}
diff --git a/src/uint256.rs b/src/uint256.rs
index 495550b..2aafd45 100644
--- a/src/uint256.rs
+++ b/src/uint256.rs
@@ -1,6 +1,7 @@
 pub use super::Int256;
 use bnum::types::U256;
 use bnum::BUint;
+use num_integer::Roots;
 use num_traits::{
     Bounded, CheckedAdd, CheckedDiv, CheckedMul, CheckedSub, FromPrimitive, Num, One, Pow,
     ToPrimitive, Zero,
@@ -66,7 +67,7 @@ impl Uint256 {
 
     /// Square root
     pub fn sqrt(&self) -> Uint256 {
-        self.0.ilog(self.0).into()
+        Self(self.0.sqrt())
     }
 }
 
@@ -357,7 +358,7 @@ macro_rules! forward_checked_op {
         impl $trait_ for $type_ {
             fn $method(&self, $type_(b): &$type_) -> Option<$type_> {
                 let $type_(a) = self;
-                let value = a.$method(*b);
+                let value = a.$method(b);
                 match value {
                     Some(value) => Some(Uint256(value)),
                     None => None,
@@ -503,7 +504,7 @@ fn check_from_str_radix_overflow() {
 /// Check the ToPrimitive impl for [0, 100k] + [2^32-100, ~2^32+100k]
 #[test]
 fn test_to_primitive_64() {
-    let u32_max: u64 = std::u32::MAX.into();
+    let u32_max: u64 = u32::MAX.into();
     use num_traits::ToPrimitive;
     let mut i = 0u64;
     while i < 100_000 {
@@ -529,7 +530,7 @@ fn test_to_primitive_64() {
 /// The default ToPrimitive impl breaks on values above 2^64
 #[test]
 fn test_to_primitive_128() {
-    let u64_max: u128 = std::u64::MAX.into();
+    let u64_max: u128 = u64::MAX.into();
     use num_traits::ToPrimitive;
     let mut i = 0u128;
     while i < 100_000 {
@@ -549,3 +550,15 @@ fn test_to_primitive_128() {
         i += 1
     }
 }
+
+#[test]
+fn test_sqrt() {
+    use rand::prelude::*;
+
+    for _ in 1..100000 {
+        let r: u128 = random();
+        let n = Uint256::from(r);
+        let sqrt = (n.mul(n)).sqrt();
+        assert!(sqrt == n);
+    }
+}