diff --git a/async/index.browser.js b/async/index.browser.js
index 402e2f4e..80d18716 100644
--- a/async/index.browser.js
+++ b/async/index.browser.js
@@ -29,7 +29,7 @@ let customAlphabet = (alphabet, defaultSize = 21) => {
     while (true) {
       let bytes = crypto.getRandomValues(new Uint8Array(step))
       // A compact alternative for `for (var i = 0; i < step; i++)`.
-      let i = step
+      let i = step | 0
       while (i--) {
         // Adding `|| ''` refuses a random byte that exceeds the alphabet size.
         id += alphabet[bytes[i] & mask] || ''
@@ -41,7 +41,7 @@ let customAlphabet = (alphabet, defaultSize = 21) => {
 
 let nanoid = async (size = 21) => {
   let id = ''
-  let bytes = crypto.getRandomValues(new Uint8Array(size))
+  let bytes = crypto.getRandomValues(new Uint8Array((size |= 0)))
 
   // A compact alternative for `for (var i = 0; i < step; i++)`.
   while (size--) {
diff --git a/async/index.js b/async/index.js
index 1e634e91..470d381f 100644
--- a/async/index.js
+++ b/async/index.js
@@ -45,7 +45,7 @@ let customAlphabet = (alphabet, defaultSize = 21) => {
       while (i--) {
         // Adding `|| ''` refuses a random byte that exceeds the alphabet size.
         id += alphabet[bytes[i] & mask] || ''
-        if (id.length === size) return id
+        if (id.length >= size) return id
       }
       return tick(id, size)
     })
@@ -54,7 +54,7 @@ let customAlphabet = (alphabet, defaultSize = 21) => {
 }
 
 let nanoid = (size = 21) =>
-  random(size).then(bytes => {
+  random((size |= 0)).then(bytes => {
     let id = ''
     // A compact alternative for `for (var i = 0; i < step; i++)`.
     while (size--) {
diff --git a/async/index.native.js b/async/index.native.js
index 0ebdacd0..239ef6fc 100644
--- a/async/index.native.js
+++ b/async/index.native.js
@@ -31,7 +31,7 @@ let customAlphabet = (alphabet, defaultSize = 21) => {
       while (i--) {
         // Adding `|| ''` refuses a random byte that exceeds the alphabet size.
         id += alphabet[bytes[i] & mask] || ''
-        if (id.length === size) return id
+        if (id.length >= size) return id
       }
       return tick(id, size)
     })
@@ -40,7 +40,7 @@ let customAlphabet = (alphabet, defaultSize = 21) => {
 }
 
 let nanoid = (size = 21) =>
-  random(size).then(bytes => {
+  random((size |= 0)).then(bytes => {
     let id = ''
     // A compact alternative for `for (var i = 0; i < step; i++)`.
     while (size--) {
diff --git a/index.browser.js b/index.browser.js
index 7ab1562c..4f3c4b4e 100644
--- a/index.browser.js
+++ b/index.browser.js
@@ -34,7 +34,7 @@ let customRandom = (alphabet, defaultSize, getRandom) => {
     while (true) {
       let bytes = getRandom(step)
       // A compact alternative for `for (var i = 0; i < step; i++)`.
-      let j = step
+      let j = step | 0
       while (j--) {
         // Adding `|| ''` refuses a random byte that exceeds the alphabet size.
         id += alphabet[bytes[j] & mask] || ''
diff --git a/index.js b/index.js
index 977f07b0..5a8a0751 100644
--- a/index.js
+++ b/index.js
@@ -23,8 +23,8 @@ let fillPool = bytes => {
 }
 
 let random = bytes => {
-  // `-=` convert `bytes` to number to prevent `valueOf` abusing
-  fillPool((bytes -= 0))
+  // `|=` convert `bytes` to number to prevent `valueOf` abusing and pool pollution
+  fillPool((bytes |= 0))
   return pool.subarray(poolOffset - bytes, poolOffset)
 }
 
@@ -67,8 +67,8 @@ let customAlphabet = (alphabet, size = 21) =>
   customRandom(alphabet, size, random)
 
 let nanoid = (size = 21) => {
-  // `-=` convert `size` to number to prevent `valueOf` abusing
-  fillPool((size -= 0))
+  // `|=` convert `size` to number to prevent `valueOf` abusing and pool pollution
+  fillPool((size |= 0))
   let id = ''
   // We are reading directly from the random pool to avoid creating new array
   for (let i = poolOffset - size; i < poolOffset; i++) {
diff --git a/non-secure/index.js b/non-secure/index.js
index 947d84fa..d51fcb6c 100644
--- a/non-secure/index.js
+++ b/non-secure/index.js
@@ -11,7 +11,7 @@ let customAlphabet = (alphabet, defaultSize = 21) => {
   return (size = defaultSize) => {
     let id = ''
     // A compact alternative for `for (var i = 0; i < step; i++)`.
-    let i = size
+    let i = size | 0
     while (i--) {
       // `| 0` is more compact and faster than `Math.floor()`.
       id += alphabet[(Math.random() * alphabet.length) | 0]
@@ -23,7 +23,7 @@ let customAlphabet = (alphabet, defaultSize = 21) => {
 let nanoid = (size = 21) => {
   let id = ''
   // A compact alternative for `for (var i = 0; i < step; i++)`.
-  let i = size
+  let i = size | 0
   while (i--) {
     // `| 0` is more compact and faster than `Math.floor()`.
     id += urlAlphabet[(Math.random() * 64) | 0]
diff --git a/test/async.test.js b/test/async.test.js
index 1ffd789a..7c01d357 100644
--- a/test/async.test.js
+++ b/test/async.test.js
@@ -1,6 +1,6 @@
 let { suite } = require('uvu')
 let { spy } = require('nanospy')
-let { is, match, ok } = require('uvu/assert')
+let { is, match, ok, not } = require('uvu/assert')
 let crypto = require('crypto')
 
 global.crypto = {
@@ -55,6 +55,13 @@ for (let type of ['node', 'browser']) {
     )
   })
 
+  nanoidSuite('avoids pool pollution, infinite loop', async () => {
+    await nanoid(2.1)
+    let second = await nanoid()
+    let third = await nanoid()
+    not.equal(second, third)
+  })
+
   nanoidSuite('changes ID length', async () => {
     let id = await nanoid(10)
     is(id.length, 10)
diff --git a/test/index.test.js b/test/index.test.js
index 9bc3350c..3dfd563a 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -1,5 +1,5 @@
 let { test } = require('uvu')
-let { is, ok, equal, match } = require('uvu/assert')
+let { is, ok, equal, match, not } = require('uvu/assert')
 
 let browser = require('../index.browser.js')
 let node = require('../index.js')
@@ -34,6 +34,13 @@ for (let type of ['node', 'browser']) {
     }
   })
 
+  test(`${type} / nanoid / avoids pool pollution, infinite loop`, () => {
+    nanoid(2.1)
+    let second = nanoid()
+    let third = nanoid()
+    not.equal(second, third)
+  })
+
   test(`${type} / nanoid / changes ID length`, () => {
     is(nanoid(10).length, 10)
   })
diff --git a/test/non-secure.test.js b/test/non-secure.test.js
index 6b6117b4..f952da64 100644
--- a/test/non-secure.test.js
+++ b/test/non-secure.test.js
@@ -1,5 +1,5 @@
 let { test } = require('uvu')
-let { is, match, ok } = require('uvu/assert')
+let { is, match, ok, not } = require('uvu/assert')
 
 let { nanoid, customAlphabet } = require('../non-secure')
 let { urlAlphabet } = require('..')
@@ -56,6 +56,13 @@ test('nanoid / has flat distribution', () => {
   ok(max - min <= 0.05)
 })
 
+test('nanoid / avoids pool pollution, infinite loop', () => {
+  nanoid(2.1)
+  let second = nanoid()
+  let third = nanoid()
+  not.equal(second, third)
+})
+
 test('customAlphabet / has options', () => {
   let nanoidA = customAlphabet('a', 5)
   is(nanoidA(), 'aaaaa')
@@ -88,4 +95,13 @@ test('customAlphabet / has flat distribution', () => {
   ok(max - min <= 0.05)
 })
 
+test('customAlphabet / avoids pool pollution, infinite loop', () => {
+  let ALPHABET = 'abcdefghijklmnopqrstuvwxyz'
+  let nanoid2 = customAlphabet(ALPHABET)
+  nanoid2(2.1)
+  let second = nanoid2()
+  let third = nanoid2()
+  not.equal(second, third)
+})
+
 test.run()
diff --git a/test/react-native-polyfill.test.js b/test/react-native-polyfill.test.js
index d6615ed7..d96e2168 100644
--- a/test/react-native-polyfill.test.js
+++ b/test/react-native-polyfill.test.js
@@ -1,5 +1,5 @@
 let { test } = require('uvu')
-let { is } = require('uvu/assert')
+let { is, not } = require('uvu/assert')
 
 test.before(() => {
   global.navigator = {
@@ -27,4 +27,12 @@ test('works with polyfill', () => {
   is(typeof nanoid(), 'string')
 })
 
+test('nanoid / avoids pool pollution, infinite loop', () => {
+  let { nanoid } = require('../index.browser')
+  nanoid(2.1)
+  let second = nanoid()
+  let third = nanoid()
+  not.equal(second, third)
+})
+
 test.run()