diff --git a/web/cashtab/src/components/Send/Send.js b/web/cashtab/src/components/Send/Send.js
--- a/web/cashtab/src/components/Send/Send.js
+++ b/web/cashtab/src/components/Send/Send.js
@@ -22,6 +22,7 @@
     toLegacy,
 } from '@components/Common/Ticker.js';
 import { Event } from '@utils/GoogleAnalytics';
+import { shouldRejectAmountInput } from '@utils/validation';
 export const BalanceHeader = styled.div`
     p {
         color: #777;
@@ -332,27 +333,13 @@
 
     const handleBchAmountChange = e => {
         const { value, name } = e.target;
-        let error = false;
         let bchValue = value;
-
-        if (selectedCurrency === 'USD') {
-            bchValue = (value / fiatPrice).toFixed(8);
-        }
-
-        // Validate value for > 0
-        if (isNaN(bchValue)) {
-            error = 'Amount must be a number';
-        } else if (bchValue <= 0) {
-            error = 'Amount must be greater than 0';
-        } else if (bchValue < currency.dust) {
-            error = `Send amount must be at least ${currency.dust} ${currency.ticker}`;
-        } else if (bchValue > balances.totalBalance) {
-            error = `Amount cannot exceed your ${currency.ticker} balance`;
-        } else if (!isNaN(bchValue) && bchValue.toString().includes('.')) {
-            if (bchValue.toString().split('.')[1].length > 8) {
-                error = `${currency.ticker} transactions do not support more than 8 decimal places`;
-            }
-        }
+        const error = shouldRejectAmountInput(
+            bchValue,
+            selectedCurrency,
+            fiatPrice,
+            balances.totalBalance,
+        );
         setSendBchAmountError(error);
 
         setFormData(p => ({ ...p, [name]: value }));
diff --git a/web/cashtab/src/utils/__tests__/validation.test.js b/web/cashtab/src/utils/__tests__/validation.test.js
new file mode 100644
--- /dev/null
+++ b/web/cashtab/src/utils/__tests__/validation.test.js
@@ -0,0 +1,74 @@
+import { shouldRejectAmountInput } from '../validation';
+import { currency } from '@components/Common/Ticker.js';
+
+describe('Validation utils', () => {
+    it(`Returns 'false' if ${currency.ticker} send amount is a valid send amount`, () => {
+        expect(shouldRejectAmountInput('10', currency.ticker, 20.0, 300)).toBe(
+            false,
+        );
+    });
+    it(`Returns 'false' if ${currency.ticker} send amount is a valid send amount in USD`, () => {
+        // Here, user is trying to send $170 USD, where 1 BCHA = $20 USD, and the user has a balance of 15 BCHA or $300
+        expect(shouldRejectAmountInput('170', 'USD', 20.0, 15)).toBe(false);
+    });
+    it(`Returns not a number if ${currency.ticker} send amount is not a number`, () => {
+        const expectedValidationError = `Amount must be a number`;
+        expect(
+            shouldRejectAmountInput('Not a number', currency.ticker, 20.0, 3),
+        ).toBe(expectedValidationError);
+    });
+    it(`Returns amount must be greater than 0 if ${currency.ticker} send amount is 0`, () => {
+        const expectedValidationError = `Amount must be greater than 0`;
+        expect(shouldRejectAmountInput('0', currency.ticker, 20.0, 3)).toBe(
+            expectedValidationError,
+        );
+    });
+    it(`Returns amount must be greater than 0 if ${currency.ticker} send amount is less than 0`, () => {
+        const expectedValidationError = `Amount must be greater than 0`;
+        expect(
+            shouldRejectAmountInput('-0.031', currency.ticker, 20.0, 3),
+        ).toBe(expectedValidationError);
+    });
+    it(`Returns balance error if ${currency.ticker} send amount is greater than user balance`, () => {
+        const expectedValidationError = `Amount cannot exceed your ${currency.ticker} balance`;
+        expect(shouldRejectAmountInput('17', currency.ticker, 20.0, 3)).toBe(
+            expectedValidationError,
+        );
+    });
+    it(`Returns balance error if ${currency.ticker} send amount is greater than user balance`, () => {
+        const expectedValidationError = `Amount cannot exceed your ${currency.ticker} balance`;
+        expect(shouldRejectAmountInput('17', currency.ticker, 20.0, 3)).toBe(
+            expectedValidationError,
+        );
+    });
+    it(`Returns error if ${currency.ticker} send amount is less than ${currency.dust} minimum`, () => {
+        const expectedValidationError = `Send amount must be at least ${currency.dust} ${currency.ticker}`;
+        expect(
+            shouldRejectAmountInput(
+                (currency.dust - 0.00000001).toString(),
+                currency.ticker,
+                20.0,
+                3,
+            ),
+        ).toBe(expectedValidationError);
+    });
+    it(`Returns error if ${currency.ticker} send amount is less than ${currency.dust} minimum in fiat currency`, () => {
+        const expectedValidationError = `Send amount must be at least ${currency.dust} ${currency.ticker}`;
+        expect(
+            shouldRejectAmountInput('0.0000005', 'USD', 14.63, 0.52574662),
+        ).toBe(expectedValidationError);
+    });
+    it(`Returns balance error if ${currency.ticker} send amount is greater than user balance with fiat currency selected`, () => {
+        const expectedValidationError = `Amount cannot exceed your ${currency.ticker} balance`;
+        // Here, user is trying to send $170 USD, where 1 BCHA = $20 USD, and the user has a balance of 5 BCHA or $100
+        expect(shouldRejectAmountInput('170', 'USD', 20.0, 5)).toBe(
+            expectedValidationError,
+        );
+    });
+    it(`Returns precision error if ${currency.ticker} send amount has more than 8 decimal places`, () => {
+        const expectedValidationError = `${currency.ticker} transactions do not support more than 8 decimal places`;
+        expect(
+            shouldRejectAmountInput('17.123456789', currency.ticker, 20.0, 35),
+        ).toBe(expectedValidationError);
+    });
+});
diff --git a/web/cashtab/src/utils/validation.js b/web/cashtab/src/utils/validation.js
new file mode 100644
--- /dev/null
+++ b/web/cashtab/src/utils/validation.js
@@ -0,0 +1,34 @@
+import { currency } from '@components/Common/Ticker.js';
+
+// Validate cash amount
+export const shouldRejectAmountInput = (
+    cashAmount,
+    selectedCurrency,
+    fiatPrice,
+    totalCashBalance,
+) => {
+    // Take cashAmount as input, a string from form input
+    let error = false;
+    let testedAmount = cashAmount;
+
+    if (selectedCurrency === 'USD') {
+        testedAmount = (cashAmount / fiatPrice).toFixed(8);
+    }
+
+    // Validate value for > 0
+    if (isNaN(testedAmount)) {
+        error = 'Amount must be a number';
+    } else if (testedAmount <= 0) {
+        error = 'Amount must be greater than 0';
+    } else if (testedAmount < currency.dust) {
+        error = `Send amount must be at least ${currency.dust} ${currency.ticker}`;
+    } else if (testedAmount > totalCashBalance) {
+        error = `Amount cannot exceed your ${currency.ticker} balance`;
+    } else if (!isNaN(testedAmount) && testedAmount.toString().includes('.')) {
+        if (testedAmount.toString().split('.')[1].length > 8) {
+            error = `${currency.ticker} transactions do not support more than 8 decimal places`;
+        }
+    }
+    // return false if no error, or string error msg if error
+    return error;
+};