diff --git a/dev/src/pages/forms.tsx b/dev/src/pages/forms.tsx
index aa47854..1af0137 100644
--- a/dev/src/pages/forms.tsx
+++ b/dev/src/pages/forms.tsx
@@ -76,6 +76,10 @@ export default function FormsPage() {
                         prefix="$"
                         suffix="USD"
                         inputMode="decimal"
+                        numberText
+                        min={50}
+                        defaultValue={50}
+                        step={5}
                     />
                     <Input
                         label="Error state"
diff --git a/src/form/Input/NumberInputButtons.tsx b/src/form/Input/NumberInputButtons.tsx
index a39e4cd..d09a0cd 100644
--- a/src/form/Input/NumberInputButtons.tsx
+++ b/src/form/Input/NumberInputButtons.tsx
@@ -1,12 +1,9 @@
 import React, { useEffect, useRef, useState } from "react";
 import Row from "../../layout/Row";
-import { Info, Minus, Plus } from "lucide-react";
+import { Minus, Plus } from "lucide-react";
 import twuiNumberfy from "../../utils/numberfy";
 import type { InputProps } from ".";
 
-let pressInterval: any;
-let pressTimeout: any;
-
 type Props = Pick<InputProps<any>, "min" | "max" | "step" | "decimal"> & {
     value: string;
     setValue: React.Dispatch<React.SetStateAction<string>>;
@@ -28,142 +25,125 @@ export default function NumberInputButtons({
     decimal,
 }: Props) {
     const PRESS_TRIGGER_TIMEOUT = 200;
+    const PRESS_REPEAT_INTERVAL = 50;
     const DEFAULT_STEP = 1;
 
     const [buttonDown, setButtonDown] = useState(false);
 
-    // function getNormalizedValue(value: string) {
-    //     if (numberText) {
-    //         if (props.max && twuiNumberfy(value) > twuiNumberfy(props.max))
-    //             return getFinalValue(props.max);
-
-    //         if (props.min && twuiNumberfy(value) < twuiNumberfy(props.min))
-    //             return getFinalValue(props.min);
-
-    //         return getFinalValue(value);
-    //     } else {
-    //         return value;
-    //     }
-    // }
+    // Instance scoped so holding one stepper cannot cancel another's repeat.
+    const pressTimeoutRef = useRef<any>(null);
+    const pressIntervalRef = useRef<any>(null);
+    const heldRef = useRef(false);
 
     useEffect(() => {
         buttonDownRef.current = buttonDown;
-        if (buttonDown) {
-            setValue(inputRef.current?.value || "");
-        } else {
-            setTimeout(() => {
-                setValue(inputRef.current?.value || "");
-            }, 50);
-        }
     }, [buttonDown]);
 
-    function incrementDownPress() {
-        window.clearTimeout(pressTimeout);
-        window.clearInterval(pressInterval);
-        setButtonDown(true);
+    useEffect(() => {
+        return () => {
+            clearPressTimers();
+        };
+    }, []);
 
-        pressTimeout = setTimeout(() => {
-            pressInterval = setInterval(() => {
-                increment();
-            }, 50);
-        }, PRESS_TRIGGER_TIMEOUT);
+    function isNil(v: any) {
+        return v === undefined || v === null;
     }
 
-    function incrementDownCancel() {
-        setButtonDown(false);
-        window.clearTimeout(pressTimeout);
-        window.clearInterval(pressInterval);
+    function clearPressTimers() {
+        window.clearTimeout(pressTimeoutRef.current);
+        window.clearInterval(pressIntervalRef.current);
     }
 
-    function decrementDownPress() {
-        window.clearTimeout(pressTimeout);
-        window.clearInterval(pressInterval);
-        setButtonDown(true);
+    function clamp(numberValue: number) {
+        const minValue = isNil(min) ? undefined : twuiNumberfy(min, decimal);
+        const maxValue = isNil(max) ? undefined : twuiNumberfy(max, decimal);
 
-        pressTimeout = setTimeout(() => {
-            pressInterval = setInterval(() => {
-                decrement();
-            }, 50);
-        }, PRESS_TRIGGER_TIMEOUT);
+        if (minValue !== undefined && numberValue < minValue) return minValue;
+        if (maxValue !== undefined && numberValue > maxValue) return maxValue;
+        return numberValue;
     }
 
-    function decrementDownCancel() {
-        setButtonDown(false);
-        window.clearTimeout(pressTimeout);
-        window.clearInterval(pressInterval);
+    const endsWithDecimalPoint = String(value).match(/\.$/);
+
+    function applyDelta(delta: number) {
+        setValue((previousValue) => {
+            const currentValue = twuiNumberfy(previousValue, decimal);
+            const nextValue = clamp(currentValue + delta);
+
+            // Round off float drift (e.g. 0.1 + 0.2) before stringifying.
+            const roundedValue =
+                decimal === undefined
+                    ? Number(nextValue.toFixed(10))
+                    : Number(nextValue.toFixed(decimal));
+
+            return String(roundedValue);
+        });
+    }
+
+    function stepSize() {
+        const stepValue = twuiNumberfy(step || DEFAULT_STEP, decimal);
+        return stepValue || DEFAULT_STEP;
     }
 
     function increment() {
-        if (!inputRef.current) return;
-
-        const existingValue = inputRef.current.value;
-        const existingNumberValue = twuiNumberfy(existingValue, decimal);
-
-        let new_value = "";
-
-        if (max && existingNumberValue >= twuiNumberfy(max, decimal)) {
-            new_value = twuiNumberfy(max, decimal).toLocaleString();
-        } else if (min && existingNumberValue < twuiNumberfy(min, decimal)) {
-            new_value = twuiNumberfy(min, decimal).toLocaleString();
-        } else {
-            new_value = (
-                existingNumberValue +
-                twuiNumberfy(step || DEFAULT_STEP, decimal)
-            ).toLocaleString();
-        }
-
-        inputRef.current.value = new_value;
+        if (endsWithDecimalPoint) return;
+        applyDelta(stepSize());
     }
 
     function decrement() {
-        if (!inputRef.current) return;
+        if (endsWithDecimalPoint) return;
+        applyDelta(-stepSize());
+    }
 
-        const existingValue = inputRef.current?.value;
-        const existingNumberValue = twuiNumberfy(existingValue, decimal);
+    function startPress(action: () => void) {
+        clearPressTimers();
+        heldRef.current = false;
+        setButtonDown(true);
 
-        let new_value = "";
+        pressTimeoutRef.current = setTimeout(() => {
+            heldRef.current = true;
+            pressIntervalRef.current = setInterval(action, PRESS_REPEAT_INTERVAL);
+        }, PRESS_TRIGGER_TIMEOUT);
+    }
 
-        if (min && existingNumberValue <= twuiNumberfy(min, decimal)) {
-            new_value = twuiNumberfy(min, decimal).toLocaleString();
-        } else {
-            new_value = (
-                existingNumberValue -
-                twuiNumberfy(step || DEFAULT_STEP, decimal)
-            ).toLocaleString();
+    function cancelPress() {
+        clearPressTimers();
+        setButtonDown(false);
+    }
+
+    /** A held press already stepped the value; ignore the trailing click. */
+    function handleClick(e: React.MouseEvent, action: () => void) {
+        e.preventDefault();
+        if (heldRef.current) {
+            heldRef.current = false;
+            return;
         }
-
-        inputRef.current.value = new_value;
+        action();
     }
 
     return (
         <Row className="flex-nowrap gap-1 -my-2 ml-auto -mr-2">
             <Row
                 className="rounded-full w-8 h-8 cursor-pointer touch-none select-none justify-center"
-                onClick={(e) => {
-                    e.preventDefault();
-                    decrement();
-                }}
-                onMouseDown={decrementDownPress}
-                onTouchStart={decrementDownPress}
-                onMouseUp={decrementDownCancel}
-                onMouseLeave={decrementDownCancel}
-                onTouchEnd={decrementDownCancel}
-                onTouchCancel={decrementDownCancel}
+                onClick={(e) => handleClick(e, decrement)}
+                onMouseDown={() => startPress(decrement)}
+                onTouchStart={() => startPress(decrement)}
+                onMouseUp={cancelPress}
+                onMouseLeave={cancelPress}
+                onTouchEnd={cancelPress}
+                onTouchCancel={cancelPress}
             >
                 <Minus size={20} />
             </Row>
             <Row
                 className="rounded-full w-8 h-8 cursor-pointer touch-none select-none justify-center"
-                onClick={(e) => {
-                    e.preventDefault();
-                    increment();
-                }}
-                onMouseDown={incrementDownPress}
-                onTouchStart={incrementDownPress}
-                onMouseUp={incrementDownCancel}
-                onMouseLeave={incrementDownCancel}
-                onTouchEnd={incrementDownCancel}
-                onTouchCancel={incrementDownCancel}
+                onClick={(e) => handleClick(e, increment)}
+                onMouseDown={() => startPress(increment)}
+                onTouchStart={() => startPress(increment)}
+                onMouseUp={cancelPress}
+                onMouseLeave={cancelPress}
+                onTouchEnd={cancelPress}
+                onTouchCancel={cancelPress}
             >
                 <Plus size={20} />
             </Row>
diff --git a/src/form/Input/index.tsx b/src/form/Input/index.tsx
index aee00cc..59939ec 100644
--- a/src/form/Input/index.tsx
+++ b/src/form/Input/index.tsx
@@ -42,10 +42,7 @@ export type InputProps<KeyType extends string> = Omit<
         >;
         showLabel?: boolean;
         istextarea?: boolean;
-        wrapperProps?: DetailedHTMLProps<
-            InputHTMLAttributes<HTMLDivElement>,
-            HTMLDivElement
-        >;
+        wrapperProps?: ComponentProps<"div">;
         wrapperWrapperProps?: ComponentProps<typeof Stack>;
         labelProps?: DetailedHTMLProps<
             LabelHTMLAttributes<HTMLLabelElement>,
@@ -126,10 +123,19 @@ export default function Input<KeyType extends string>(
     let timeoutRef = useRef<any>(null);
     let validationFnTimeoutRef = useRef<any>(null);
     let externalValueChangeTimeoutRef = useRef<any>(null);
+    const didMountRef = useRef(false);
 
     refreshes++;
     componentRefreshesRef.current++;
 
+    React.useEffect(() => {
+        return () => {
+            window.clearTimeout(timeoutRef.current);
+            window.clearTimeout(validationFnTimeoutRef.current);
+            window.clearTimeout(externalValueChangeTimeoutRef.current);
+        };
+    }, []);
+
     function getFinalValue(v: any) {
         if (rawNumber) return twuiNumberfy(v);
         if (numberText) {
@@ -142,10 +148,17 @@ export default function Input<KeyType extends string>(
         return v;
     }
 
-    const defaultInitialValue =
-        props.defaultValue || props.value
-            ? getFinalValue(props.defaultValue || props.value)
-            : undefined;
+    /** `defaultValue`/`value` of `0` or `""` is valid input, so compare against
+     * `undefined`/`null` instead of relying on truthiness. */
+    const initialValue = !isNil(props.defaultValue)
+        ? props.defaultValue
+        : !isNil(props.value)
+          ? props.value
+          : undefined;
+
+    const defaultInitialValue = isNil(initialValue)
+        ? undefined
+        : getFinalValue(initialValue);
 
     const [validity, setValidity] = React.useState<TWUISelectValidityObject>(
         existingValidity || {
@@ -160,7 +173,7 @@ export default function Input<KeyType extends string>(
     const buttonDownRef = React.useRef(false);
 
     const [value, setValue] = React.useState(
-        props.defaultValue ? String(props.defaultValue) : "",
+        isNil(initialValue) ? "" : String(initialValue),
     );
     const [focus, setFocus] = React.useState(false);
     const [inputType, setInputType] = React.useState(
@@ -188,8 +201,6 @@ export default function Input<KeyType extends string>(
     }, [existingValidity]);
 
     const updateValueFn = (val: string) => {
-        if (buttonDownRef.current) return;
-
         if (changeHandler) {
             window.clearTimeout(externalValueChangeTimeoutRef.current);
             externalValueChangeTimeoutRef.current = setTimeout(() => {
@@ -199,7 +210,9 @@ export default function Input<KeyType extends string>(
 
         if (typeof val == "string") {
             if (!val.match(/./)) {
-                setValidity({ isValid: true });
+                // An externally supplied `validity` stays authoritative, so a
+                // cleared `required` field is not reported as valid.
+                if (!existingValidity) setValidity({ isValid: true });
                 setValue("");
                 if (istextarea && textAreaRef.current) {
                     textAreaRef.current.value = "";
@@ -215,7 +228,7 @@ export default function Input<KeyType extends string>(
                 timeoutRef.current = setTimeout(() => {
                     setValidity({
                         isValid: validationRegex.test(val),
-                        msg: "Value mismatch",
+                        msg: initialInvalidMessage ?? "Value mismatch",
                     });
                 }, finalDebounce);
             }
@@ -250,11 +263,17 @@ export default function Input<KeyType extends string>(
     // }, [refreshDefaultValue]);
 
     React.useEffect(() => {
-        // if (!existingReady) return;
-        if (istextarea && textAreaRef.current) {
-        } else if (inputRef?.current) {
-            inputRef.current.value = getFinalValue(value);
+        const element = istextarea ? textAreaRef.current : inputRef?.current;
+        if (element) element.value = getFinalValue(value);
+
+        if (!didMountRef.current) {
+            didMountRef.current = true;
+            // Do not validate the mount value: an external `validity` prop owns
+            // the initial state until the user actually edits the field.
+            if (!existingValidity) updateValueFn(value);
+            return;
         }
+
         updateValueFn(value);
     }, [value]);
 
@@ -363,9 +382,6 @@ export default function Input<KeyType extends string>(
                     "relative flex items-center gap-2 rounded-default px-3 py-2 outline-1",
                     "hover:[&_.twui-clear-input-field-button]:opacity-100",
                     "w-full border-none",
-                    focus && validity.isValid
-                        ? "outline-slate-700 dark:outline-white/50"
-                        : "outline-slate-300 dark:outline-white/20",
                     focus && validity.isValid
                         ? "outline-slate-700 dark:outline-white/50"
                         : "outline-slate-300 dark:outline-white/20",
@@ -393,8 +409,8 @@ export default function Input<KeyType extends string>(
             >
                 {showLabel && (
                     <label
-                        htmlFor={props.name}
                         {...labelProps}
+                        htmlFor={labelProps?.htmlFor || props.name}
                         className={twMerge(
                             "text-xs absolute -top-2.5 left-2 text-foreground-light/80 bg-background-light",
                             "dark:text-foreground-dark/80 dark:bg-background-dark whitespace-nowrap",
@@ -555,6 +571,10 @@ export default function Input<KeyType extends string>(
 
 const PICKER_INPUT_TYPES = ["date", "datetime-local", "time", "month", "week"];
 
+function isNil(value: unknown): value is undefined | null {
+    return value === undefined || value === null;
+}
+
 function setNativeInputValue(
     element: HTMLInputElement | HTMLTextAreaElement,
     newValue: string,