diff --git a/api/resolvers/wallet.js b/api/resolvers/wallet.js
index 8d028514b..0d1d08166 100644
--- a/api/resolvers/wallet.js
+++ b/api/resolvers/wallet.js
@@ -63,9 +63,9 @@ const resolvers = {
 
 export default resolvers
 
-export async function createWithdrawal (parent, { invoice, maxFee }, { me, models, lnd, headers, protocol, logger }) {
+export async function createWithdrawal (parent, { invoice, maxFee, amount }, { me, models, lnd, headers, protocol, logger }) {
   assertApiKeyNotPermitted({ me })
-  await validateSchema(withdrawlSchema, { invoice, maxFee })
+  await validateSchema(withdrawlSchema, { invoice, maxFee, amount })
   await assertGofacYourself({ models, headers })
 
   // remove 'lightning:' prefix if present
@@ -95,7 +95,10 @@ export async function createWithdrawal (parent, { invoice, maxFee }, { me, model
   }
 
   if (!decoded.mtokens || BigInt(decoded.mtokens) <= 0) {
-    throw new GqlInputError('invoice must specify an amount')
+    if (!amount) {
+      throw new GqlInputError('invoice must specify an amount')
+    }
+    decoded.mtokens = BigInt(amount) * 1000n
   }
 
   if (decoded.mtokens > Number.MAX_SAFE_INTEGER) {
diff --git a/api/typeDefs/wallet.js b/api/typeDefs/wallet.js
index 95d4640eb..5ced5075f 100644
--- a/api/typeDefs/wallet.js
+++ b/api/typeDefs/wallet.js
@@ -13,7 +13,7 @@ const typeDefs = gql`
   }
 
   extend type Mutation {
-    createWithdrawl(invoice: String!, maxFee: Int!): PayIn!
+    createWithdrawl(invoice: String!, maxFee: Int!, amount: Int): PayIn!
     sendToLnAddr(addr: String!, amount: Int!, maxFee: Int!, comment: String, identifier: Boolean, name: String, email: String): PayIn!
     dropBolt11(hash: String!): Boolean
     buyCredits(credits: Int!): PayIn!
diff --git a/fragments/withdrawal.js b/fragments/withdrawal.js
index 4df98ca03..38cf002df 100644
--- a/fragments/withdrawal.js
+++ b/fragments/withdrawal.js
@@ -1,8 +1,8 @@
 import { gql } from '@apollo/client'
 
 export const CREATE_WITHDRAWL = gql`
-  mutation createWithdrawl($invoice: String!, $maxFee: Int!) {
-    createWithdrawl(invoice: $invoice, maxFee: $maxFee) {
+  mutation createWithdrawl($invoice: String!, $maxFee: Int!, $amount: Int) {
+    createWithdrawl(invoice: $invoice, maxFee: $maxFee, amount: $amount) {
       id
     }
 }`
diff --git a/lib/validate.js b/lib/validate.js
index dc6d47ce5..3de0486e4 100644
--- a/lib/validate.js
+++ b/lib/validate.js
@@ -490,7 +490,8 @@ export const lastAuthRemovalSchema = object({
 
 export const withdrawlSchema = object({
   invoice: string().required('required').trim(),
-  maxFee: intValidator.required('required').min(0, 'must be at least 0')
+  maxFee: intValidator.required('required').min(0, 'must be at least 0'),
+  amount: intValidator.optional().min(1, 'must be at least 1 sat')
 })
 
 export const bioSchema = object({
diff --git a/pages/withdraw.js b/pages/withdraw.js
index 4cdc3280f..dcb0984cc 100644
--- a/pages/withdraw.js
+++ b/pages/withdraw.js
@@ -7,7 +7,7 @@ import styles from '@/styles/nav.module.css'
 import { useMutation } from '@apollo/client'
 import { CREATE_WITHDRAWL, SEND_TO_LNADDR } from '@/fragments/withdrawal'
 import { requestProvider } from 'webln'
-import { useEffect, useState } from 'react'
+import { useEffect, useState, useCallback } from 'react'
 import { useMe } from '@/components/me'
 import { Checkbox, Form, Input, InputUserSuggest, SubmitButton } from '@/components/form'
 import { lnAddrSchema, withdrawlSchema } from '@/lib/validate'
@@ -82,6 +82,15 @@ export function InvWithdrawal () {
   const [createWithdrawl] = useMutation(CREATE_WITHDRAWL)
 
   const maxFeeDefault = me?.privates?.withdrawMaxFeeDefault
+  const [zeroAmount, setZeroAmount] = useState(false)
+  const checkInvoice = useCallback((invoice) => {
+    try {
+      const decoded = decode(invoice)
+      setZeroAmount(!decoded.mtokens || BigInt(decoded.mtokens) <= 0)
+    } catch {
+      setZeroAmount(false)
+    }
+  }, [])
 
   useEffect(() => {
     async function effect () {
@@ -106,11 +115,14 @@ export function InvWithdrawal () {
         autoComplete='off'
         initial={{
           invoice: '',
-          maxFee: maxFeeDefault
+          maxFee: maxFeeDefault,
+          amount: ''
         }}
         schema={withdrawlSchema}
-        onSubmit={async ({ invoice, maxFee }) => {
-          const { data } = await createWithdrawl({ variables: { invoice, maxFee: Number(maxFee) } })
+        onSubmit={async ({ invoice, maxFee, amount }) => {
+          const variables = { invoice, maxFee: Number(maxFee) }
+          if (zeroAmount) variables.amount = Number(amount)
+          const { data } = await createWithdrawl({ variables })
           router.push(`/transactions/${data.createWithdrawl.id}`)
         }}
       >
@@ -120,8 +132,18 @@ export function InvWithdrawal () {
           required
           autoFocus
           clear
-          append={<InvoiceScanner fieldName='invoice' />}
+          append={<InvoiceScanner fieldName='invoice' onInvoiceChange={checkInvoice} />}
+          onChange={(_, e) => { checkInvoice(e.target.value) }}
         />
+        {zeroAmount && (
+          <Input
+            label='amount (sats)'
+            name='amount'
+            type='number'
+            required
+            min={1}
+          />
+        )}
         <Input
           label='max fee'
           name='maxFee'
@@ -136,7 +158,7 @@ export function InvWithdrawal () {
   )
 }
 
-function InvoiceScanner ({ fieldName }) {
+function InvoiceScanner ({ fieldName, onInvoiceChange }) {
   const showModal = useShowModal()
   const [,, helpers] = useField(fieldName)
   const toaster = useToast()
@@ -157,13 +179,22 @@ function InvoiceScanner ({ fieldName }) {
                   formats={['qr_code']}
                   onScan={([{ rawValue: result }]) => {
                     result = result.toLowerCase()
-                    if (result.split('lightning=')[1]) {
-                      helpers.setValue(result.split('lightning=')[1].split(/[&?]/)[0])
-                    } else if (decode(result.replace(/^lightning:/, ''))) {
-                      helpers.setValue(result.replace(/^lightning:/, ''))
+                    let invoice
+                    if (result.includes('lightning=')) {
+                      invoice = result.split('lightning=')[1].split(/[&?]/)[0]
+                      helpers.setValue(invoice)
                     } else {
-                      throw new Error('Not a proper lightning payment request')
+                      try {
+                        invoice = result.replace(/^lightning:/, '')
+                        decode(invoice)
+                        helpers.setValue(invoice)
+                      } catch {
+                        toaster.danger('Not a proper lightning payment request')
+                        onClose()
+                        return
+                      }
                     }
+                    if (onInvoiceChange) onInvoiceChange(invoice)
                     onClose()
                   }}
                   styles={{