diff --git a/src/compound/struct.ts b/src/compound/struct.ts
index fbdeea5..00dc858 100644
--- a/src/compound/struct.ts
+++ b/src/compound/struct.ts
@@ -4,6 +4,7 @@ import {
   type Options,
   type Packed,
 } from "../types/mod.ts";
+import { getBiggestAlignment } from "../util.ts";
 
 export class Struct<
   T extends Record<string, AlignedType<unknown>>,
@@ -14,10 +15,7 @@ export class Struct<
   #record: Array<[string, AlignedType<unknown>]>;
 
   constructor(input: T) {
-    // Find biggest alignment
-    const byteAlignment = Object.values(input)
-      .reduce((acc, x) => Math.max(acc, x.byteAlignment), 0);
-    super(byteAlignment);
+    super(getBiggestAlignment(input));
     this.#record = Object.entries(input);
   }
 
diff --git a/src/compound/tagged_union.ts b/src/compound/tagged_union.ts
index 76719d8..d23b9cd 100644
--- a/src/compound/tagged_union.ts
+++ b/src/compound/tagged_union.ts
@@ -6,6 +6,7 @@ import {
   type Packed,
   type ValueOf,
 } from "../types/mod.ts";
+import { getBiggestAlignment } from "../util.ts";
 
 type Fn<T> = (value: T) => number;
 
@@ -19,11 +20,12 @@ export class TaggedUnion<
   #variantFinder: Fn<V>;
   #discriminant: AlignedType<number>;
 
-  constructor(input: T, variantFinder: Fn<V>, discriminantCodec: AlignedType<number> = u8) {
-    // Find biggest alignment
-    const byteAlignment = Object.values(input)
-      .reduce((acc, x) => Math.max(acc, x.byteAlignment), 0);
-    super(byteAlignment);
+  constructor(
+    input: T,
+    variantFinder: Fn<V>,
+    discriminantCodec: AlignedType<number> = u8,
+  ) {
+    super(getBiggestAlignment(input));
     this.#record = input;
     this.#variantFinder = variantFinder;
     this.#discriminant = discriminantCodec;
diff --git a/src/compound/tuple.ts b/src/compound/tuple.ts
index 96dc9c9..a9a9938 100644
--- a/src/compound/tuple.ts
+++ b/src/compound/tuple.ts
@@ -4,6 +4,7 @@ import {
   type Options,
   type Packed,
 } from "../types/mod.ts";
+import { getBiggestAlignment } from "../util.ts";
 
 export class Tuple<
   T extends [...AlignedType<unknown>[]],
@@ -12,10 +13,7 @@ export class Tuple<
   #tupleTypes: T;
 
   constructor(types: T) {
-    // Find biggest alignment
-    const byteAlignment = Object.values(types)
-      .reduce((acc, x) => Math.max(acc, x.byteAlignment), 0);
-    super(byteAlignment);
+    super(getBiggestAlignment(types));
     this.#tupleTypes = types;
   }
 
diff --git a/src/util.ts b/src/util.ts
index ba56a79..07976bb 100644
--- a/src/util.ts
+++ b/src/util.ts
@@ -1,3 +1,5 @@
+import type { AlignedType } from "./mod.ts";
+
 /**
  * The endianess of your machine, true if little endian and false if big endian.
  */
@@ -9,3 +11,11 @@ export const isLittleEndian = (() => {
 
 export const align = (unaligned: number, alignment: number) =>
   (unaligned + alignment - 1) & ~(alignment - 1);
+
+type ArrayOrRecord<T> = T[] | Record<string | number, T>;
+
+export const getBiggestAlignment = (
+  input: ArrayOrRecord<AlignedType<unknown>>,
+) =>
+  Object.values(input)
+    .reduce((acc, x) => Math.max(acc, x.byteAlignment), 0);