diff --git a/2020/18/input.txt b/2020/18/input.txt
new file mode 100644
index 0000000..dd473c0
--- /dev/null
+++ b/2020/18/input.txt
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\ No newline at end of file
diff --git a/2020/18/part1.js b/2020/18/part1.js
new file mode 100644
index 0000000..750a327
--- /dev/null
+++ b/2020/18/part1.js
@@ -0,0 +1,26 @@
+const fs = require('fs');
+const expressions = fs.readFileSync('./input.txt', 'utf-8').split('\n');
+
+function calc (expression) {
+  // if it's just a number, do nothing
+  if (!isNaN(Number(expression))) { Number(expression) }
+  // if there's brackets, do that first
+  while (expression.match(/\(/)){
+    expression = expression.replace(/\([^()]+\)/, match => 
+      calc (match.slice(1, match.length-1))
+    )
+  }
+  // do all the calculations until it's just a number
+  while (isNaN(Number(expression))) {
+    expression = expression.replace(/(\d+) ([+*]) (\d+)/, (match, a, op, b) => 
+      op == '+' ? parseInt(a) + parseInt(b) : parseInt(a) * parseInt(b)
+    )
+  }
+  return Number(expression)
+}
+
+let runningTotal = 0
+for (expression of expressions) {
+  runningTotal += calc (expression)
+}
+console.log(runningTotal)
\ No newline at end of file
diff --git a/2020/18/part2.js b/2020/18/part2.js
new file mode 100644
index 0000000..633ee7c
--- /dev/null
+++ b/2020/18/part2.js
@@ -0,0 +1,32 @@
+const fs = require('fs');
+const expressions = fs.readFileSync('./input.txt', 'utf-8').split('\n');
+
+function calc (expression) {
+  // if it's just a number, do nothing
+  if (!isNaN(Number(expression))) { Number(expression) }
+  // if there's brackets, do that first
+  while (expression.match(/\(/)){
+    expression = expression.replace(/\([^()]+\)/, match => 
+      calc (match.slice(1, match.length-1))
+    )
+  }
+  // if there's addition, do that
+  while (expression.match(/\+/)){
+    expression = expression.replace(/(\d+) \+ (\d+)/, (match, a, b) => 
+      parseInt(a) + parseInt(b)
+    )
+  }
+  // if there's multiplication, do that
+  while (expression.match(/\*/)) {
+    expression = expression.replace(/(\d+) \* (\d+)/, (match, a, b) => 
+      parseInt(a) * parseInt(b)
+    )
+  }
+  return Number(expression)
+}
+
+let runningTotal = 0
+for (expression of expressions) {
+  runningTotal += calc (expression)
+}
+console.log(runningTotal)
\ No newline at end of file
diff --git a/2020/18/test1.txt b/2020/18/test1.txt
new file mode 100644
index 0000000..2d85adb
--- /dev/null
+++ b/2020/18/test1.txt
@@ -0,0 +1,6 @@
+1 + 2 * 3 + 4 * 5 + 6
+1 + (2 * 3) + (4 * (5 + 6))
+2 * 3 + (4 * 5)
+5 + (8 * 3 + 9 + 3 * 4 * 3)
+5 * 9 * (7 * 3 * 3 + 9 * 3 + (8 + 6 * 4))
+((2 + 4 * 9) * (6 + 9 * 8 + 6) + 6) + 2 + 4 * 2
\ No newline at end of file
diff --git a/README.md b/README.md
index 221b267..9c260e7 100644
--- a/README.md
+++ b/README.md
@@ -58,3 +58,4 @@ if (advent) {
 15. [:star: :star:](https://adventofcode.com/2020/day/15 "see puzzle")
 16. [:star: :star:](https://adventofcode.com/2020/day/16 "see puzzle")
 17. [:star: :star:](https://adventofcode.com/2020/day/17 "see puzzle")
+18. [:star: :star:](https://adventofcode.com/2020/day/18 "see puzzle")