diff --git a/README.md b/README.md
index 3619723..98311ec 100644
--- a/README.md
+++ b/README.md
@@ -89,6 +89,7 @@ public:
 
     vec_base();
     explicit vec_base(uninit_t);
+    explicit vec_base(zero_init_t);
 
     explicit vec_base(T v);
     vec_base(T x, T y);
@@ -101,6 +102,7 @@ public:
 
     vec_base();
     explicit vec_base(uninit_t);
+    explicit vec_base(zero_init_t);
 
     explicit vec_base(T v);
     vec_base(T x, T y, T z);
@@ -117,6 +119,7 @@ public:
 
     vec_base();
     explicit vec_base(uninit_t);
+    explicit vec_base(zero_init_t);
 
     explicit vec_base(T v);
     vec_base(T x, T y, T z, T w);
@@ -221,6 +224,8 @@ public:
 
     mat_base();
     explicit mat_base(uninit_t);
+    explicit mat_base(zero_init_t);
+    explicit mat_base(identity_init_t);
 
     explicit mat_base(T d);
     explicit mat_base(const row_type& d);
@@ -242,6 +247,8 @@ public:
 
     mat_base();
     explicit mat_base(uninit_t);
+    explicit mat_base(zero_init_t);
+    explicit mat_base(identity_init_t);
 
     explicit mat_base(T d);
     explicit mat_base(const row_type& d);
@@ -273,6 +280,8 @@ public:
 
     mat_base();
     explicit mat_base(uninit_t);
+    explicit mat_base(zero_init_t);
+    explicit mat_base(identity_init_t);
 
     explicit mat_base(T d);
     explicit mat_base(const row_type& d);
@@ -389,6 +398,8 @@ public:
 
     qua_base();
     explicit qua_base(uninit_t);
+    explicit qua_base(zero_init_t);
+    explicit qua_base(identity_init_t);
 
     qua_base(T vx, T vy, T vz, T s);
     qua_base(const vec<T, 3>& v, T s);
diff --git a/headers/vmath.hpp/vmath_fwd.hpp b/headers/vmath.hpp/vmath_fwd.hpp
index e0ff237..6e80b56 100644
--- a/headers/vmath.hpp/vmath_fwd.hpp
+++ b/headers/vmath.hpp/vmath_fwd.hpp
@@ -42,6 +42,12 @@ namespace vmath_hpp
 {
     struct uninit_t { explicit uninit_t() = default; };
     inline constexpr uninit_t uninit{};
+
+    struct zero_init_t { explicit zero_init_t() = default; };
+    inline constexpr zero_init_t zero_init{};
+
+    struct identity_init_t { explicit identity_init_t() = default; };
+    inline constexpr identity_init_t identity_init{};
 }
 
 namespace vmath_hpp
diff --git a/headers/vmath.hpp/vmath_mat.hpp b/headers/vmath.hpp/vmath_mat.hpp
index 4993d24..0d8a0b4 100644
--- a/headers/vmath.hpp/vmath_mat.hpp
+++ b/headers/vmath.hpp/vmath_mat.hpp
@@ -23,12 +23,20 @@ namespace vmath_hpp::detail
         row_type rows[2];
     public:
         constexpr mat_base()
+        : mat_base(identity_init) {}
+
+        constexpr explicit mat_base(uninit_t) {}
+
+        constexpr explicit mat_base(zero_init_t)
+        : rows{
+            {T{0}, T{0}},
+            {T{0}, T{0}}} {}
+
+        constexpr explicit mat_base(identity_init_t)
         : rows{
             {T{1}, T{0}},
             {T{0}, T{1}}} {}
 
-        constexpr explicit mat_base(uninit_t) {}
-
         constexpr explicit mat_base(T d)
         : rows{
             {d, T{0}},
@@ -59,13 +67,22 @@ namespace vmath_hpp::detail
         row_type rows[3];
     public:
         constexpr mat_base()
+        : mat_base(identity_init) {}
+
+        constexpr explicit mat_base(uninit_t) {}
+
+        constexpr explicit mat_base(zero_init_t)
+        : rows{
+            {T{0}, T{0}, T{0}},
+            {T{0}, T{0}, T{0}},
+            {T{0}, T{0}, T{0}}} {}
+
+        constexpr explicit mat_base(identity_init_t)
         : rows{
             {T{1}, T{0}, T{0}},
             {T{0}, T{1}, T{0}},
             {T{0}, T{0}, T{1}}} {}
 
-        constexpr explicit mat_base(uninit_t) {}
-
         constexpr explicit mat_base(T d)
         : rows{
             {d, T{0}, T{0}},
@@ -122,14 +139,24 @@ namespace vmath_hpp::detail
         row_type rows[4];
     public:
         constexpr mat_base()
+        : mat_base(identity_init) {}
+
+        constexpr explicit mat_base(uninit_t) {}
+
+        constexpr explicit mat_base(zero_init_t)
+        : rows{
+            {T{0}, T{0}, T{0}, T{0}},
+            {T{0}, T{0}, T{0}, T{0}},
+            {T{0}, T{0}, T{0}, T{0}},
+            {T{0}, T{0}, T{0}, T{0}}} {}
+
+        constexpr explicit mat_base(identity_init_t)
         : rows{
             {T{1}, T{0}, T{0}, T{0}},
             {T{0}, T{1}, T{0}, T{0}},
             {T{0}, T{0}, T{1}, T{0}},
             {T{0}, T{0}, T{0}, T{1}}} {}
 
-        constexpr explicit mat_base(uninit_t) {}
-
         constexpr explicit mat_base(T d)
         : rows{
             {d, T{0}, T{0}, T{0}},
diff --git a/headers/vmath.hpp/vmath_qua.hpp b/headers/vmath.hpp/vmath_qua.hpp
index 531ff09..e74a493 100644
--- a/headers/vmath.hpp/vmath_qua.hpp
+++ b/headers/vmath.hpp/vmath_qua.hpp
@@ -20,10 +20,16 @@ namespace vmath_hpp::detail
         T s;
     public:
         constexpr qua_base()
-        : v{T{0}}, s{1} {}
+        : qua_base(identity_init) {}
 
         constexpr explicit qua_base(uninit_t) {}
 
+        constexpr explicit qua_base(zero_init_t)
+        : v{T{0}}, s{0} {}
+
+        constexpr explicit qua_base(identity_init_t)
+        : v{T{0}}, s{1} {}
+
         constexpr qua_base(T vx, T vy, T vz, T s)
         : v{vx, vy, vz}, s{s} {}
 
diff --git a/headers/vmath.hpp/vmath_vec.hpp b/headers/vmath.hpp/vmath_vec.hpp
index b2f3042..f353a40 100644
--- a/headers/vmath.hpp/vmath_vec.hpp
+++ b/headers/vmath.hpp/vmath_vec.hpp
@@ -19,10 +19,13 @@ namespace vmath_hpp::detail
         T x, y;
     public:
         constexpr vec_base()
-        : x{0}, y{0} {}
+        : vec_base(zero_init) {}
 
         constexpr explicit vec_base(uninit_t) {}
 
+        constexpr explicit vec_base(zero_init_t)
+        : x{0}, y{0} {}
+
         constexpr explicit vec_base(T v)
         : x{v}, y{v} {}
 
@@ -52,10 +55,13 @@ namespace vmath_hpp::detail
         T x, y, z;
     public:
         constexpr vec_base()
-        : x{0}, y{0}, z{0} {}
+        : vec_base(zero_init) {}
 
         constexpr explicit vec_base(uninit_t) {}
 
+        constexpr explicit vec_base(zero_init_t)
+        : x{0}, y{0}, z{0} {}
+
         constexpr explicit vec_base(T v)
         : x{v}, y{v}, z{v} {}
 
@@ -97,10 +103,13 @@ namespace vmath_hpp::detail
         T x, y, z, w;
     public:
         constexpr vec_base()
-        : x{0}, y{0}, z{0}, w{0} {}
+        : vec_base(zero_init) {}
 
         constexpr explicit vec_base(uninit_t) {}
 
+        constexpr explicit vec_base(zero_init_t)
+        : x{0}, y{0}, z{0}, w{0} {}
+
         constexpr explicit vec_base(T v)
         : x{v}, y{v}, z{v}, w{v} {}
 
diff --git a/untests/vmath_mat_tests.cpp b/untests/vmath_mat_tests.cpp
index 99b15c3..a40fd59 100644
--- a/untests/vmath_mat_tests.cpp
+++ b/untests/vmath_mat_tests.cpp
@@ -55,6 +55,22 @@ TEST_CASE("vmath/mat") {
             CHECK(m4.rows[1] == int4(0,1,0,0));
             CHECK(m4.rows[2] == int4(0,0,1,0));
             CHECK(m4.rows[3] == int4(0,0,0,1));
+
+            STATIC_CHECK(int2x2() == int2x2({1,0},{0,1}));
+            STATIC_CHECK(int3x3() == int3x3({1,0,0},{0,1,0},{0,0,1}));
+            STATIC_CHECK(int4x4() == int4x4({1,0,0,0},{0,1,0,0},{0,0,1,0},{0,0,0,1}));
+
+            (void)int2x2(uninit);
+            (void)int3x3(uninit);
+            (void)int4x4(uninit);
+
+            STATIC_CHECK(int2x2(zero_init) == int2x2({0,0},{0,0}));
+            STATIC_CHECK(int3x3(zero_init) == int3x3({0,0,0},{0,0,0},{0,0,0}));
+            STATIC_CHECK(int4x4(zero_init) == int4x4({0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0}));
+
+            STATIC_CHECK(int2x2(identity_init) == int2x2({1,0},{0,1}));
+            STATIC_CHECK(int3x3(identity_init) == int3x3({1,0,0},{0,1,0},{0,0,1}));
+            STATIC_CHECK(int4x4(identity_init) == int4x4({1,0,0,0},{0,1,0,0},{0,0,1,0},{0,0,0,1}));
         }
         {
             STATIC_CHECK(int2x2()[0] == int2(1,0));
diff --git a/untests/vmath_qua_tests.cpp b/untests/vmath_qua_tests.cpp
index 99b20af..f6103ac 100644
--- a/untests/vmath_qua_tests.cpp
+++ b/untests/vmath_qua_tests.cpp
@@ -34,6 +34,11 @@ TEST_CASE("vmath/qua") {
             qua<int> q;
             CHECK(q.v == int3(0,0,0));
             CHECK(q.s == 1);
+
+            STATIC_CHECK(qua<int>() == qua<int>({0,0,0},1));
+            (void)qua<int>(uninit);
+            STATIC_CHECK(qua<int>(zero_init) == qua<int>({0,0,0},0));
+            STATIC_CHECK(qua<int>(identity_init) == qua<int>({0,0,0},1));
         }
         {
             STATIC_CHECK(qfloat{}.v == uapprox3(0.f));
diff --git a/untests/vmath_vec_tests.cpp b/untests/vmath_vec_tests.cpp
index 59785d8..4f41421 100644
--- a/untests/vmath_vec_tests.cpp
+++ b/untests/vmath_vec_tests.cpp
@@ -55,6 +55,18 @@ TEST_CASE("vmath/vec") {
             CHECK(i4.y == 0);
             CHECK(i4.z == 0);
             CHECK(i4.w == 0);
+
+            STATIC_CHECK(int2() == int2(0,0));
+            STATIC_CHECK(int3() == int3(0,0,0));
+            STATIC_CHECK(int4() == int4(0,0,0,0));
+
+            (void)int2(uninit);
+            (void)int3(uninit);
+            (void)int4(uninit);
+
+            STATIC_CHECK(int2(zero_init) == int2(0,0));
+            STATIC_CHECK(int3(zero_init) == int3(0,0,0));
+            STATIC_CHECK(int4(zero_init) == int4(0,0,0,0));
         }
         {
             STATIC_CHECK(int2().x == 0);