diff --git a/src/components/ExpressionEditor.vue b/src/components/ExpressionEditor.vue
new file mode 100644
index 0000000..3fc394b
--- /dev/null
+++ b/src/components/ExpressionEditor.vue
@@ -0,0 +1,187 @@
+<template>
+  <div class="code-editor">
+      <input class="code-input"
+                :value="value"
+                @input="updateValue($event.target.value)"
+                @keydown="handleKeyDown"
+                @scroll="handleScroll"
+                ref="codeEditor"/>
+      <div v-if="showSuggestions" class="suggestions-box" :style="suggestionsBoxStyle">
+          <div v-for="(suggestion, index) in filteredSuggestions"
+                :key="index"
+                @click="applySuggestion(suggestion)"
+                @mouseover="selectedIndex = index"
+                class="suggestion-item"
+                :class="{ selected: index === selectedIndex }">
+              {{ suggestion }}
+          </div>
+      </div>
+  </div>
+</template>
+
+<script>
+export default {
+    props: {
+        value: String,
+        suggestions: {
+            type: Array,
+            default: () => []
+        }
+    },
+    data () {
+        return {
+            filteredSuggestions: [],
+            showSuggestions: false,
+            selectedIndex: 0,
+            currentWord: '',
+            cursorPosition: { top: 0, left: 0 },
+            scrollTop: 0
+        }
+    },
+    computed: {
+        suggestionsBoxStyle () {
+            return {
+                top: `${this.cursorPosition.top - this.scrollTop + 20}px`,
+                left: `${this.cursorPosition.left}px`
+            }
+        }
+    },
+    methods: {
+        updateValue (value) {
+            this.$emit('input', value)
+            this.handleInput()
+        },
+        handleInput () {
+            const cursorPosition = this.$refs.codeEditor.selectionStart
+            const textBeforeCursor = this.value.slice(0, cursorPosition)
+            const words = textBeforeCursor.split(/\s+/)
+            this.currentWord = words[words.length - 1]
+
+            if (this.currentWord.length > 0) {
+                this.filteredSuggestions = this.suggestions.filter(s =>
+                    s.toLowerCase().startsWith(this.currentWord.toLowerCase())
+                )
+                this.showSuggestions = this.filteredSuggestions.length > 0
+                this.selectedIndex = 0
+                this.updateCursorPosition()
+            } else {
+                this.showSuggestions = false
+            }
+        },
+        handleKeyDown (e) {
+            if (this.showSuggestions) {
+                switch (e.key) {
+                case 'ArrowDown':
+                    e.preventDefault()
+                    this.selectedIndex = (this.selectedIndex + 1) % this.filteredSuggestions.length
+                    break
+                case 'ArrowUp':
+                    e.preventDefault()
+                    this.selectedIndex = (this.selectedIndex - 1 + this.filteredSuggestions.length) %
+                     this.filteredSuggestions.length
+                    break
+                case 'Enter':
+                case 'Tab':
+                    e.preventDefault()
+                    this.applySuggestion(this.filteredSuggestions[this.selectedIndex])
+                    break
+                case 'Escape':
+                    this.showSuggestions = false
+                    break
+                }
+            }
+        },
+        applySuggestion (suggestion) {
+            const cursorPosition = this.$refs.codeEditor.selectionStart
+            const textBeforeCursor = this.value.slice(0, cursorPosition)
+            const textAfterCursor = this.value.slice(cursorPosition)
+            const lastSpaceIndex = textBeforeCursor.lastIndexOf(' ')
+            const newTextBeforeCursor = textBeforeCursor.slice(0, lastSpaceIndex + 1) + suggestion
+
+            const newValue = newTextBeforeCursor + textAfterCursor
+            this.updateValue(newValue)
+
+            this.$nextTick(() => {
+                this.$refs.codeEditor.selectionStart = this.$refs.codeEditor.selectionEnd = newTextBeforeCursor.length
+                this.$refs.codeEditor.focus()
+            })
+
+            this.showSuggestions = false
+        },
+        updateCursorPosition () {
+            const textarea = this.$refs.codeEditor
+            const cursorPosition = textarea.selectionStart
+            const textBeforeCursor = this.value.slice(0, cursorPosition)
+            // const lines = textBeforeCursor.split('\n')
+            // const currentLine = lines.length
+            // const currentLineText = lines[lines.length - 1]
+
+            const temp = document.createElement('div')
+            temp.style.position = 'absolute'
+            temp.style.top = '-9999px'
+            temp.style.left = '-9999px'
+            temp.style.width = textarea.clientWidth + 'px'
+            temp.style.height = 'auto'
+            temp.style.whiteSpace = 'pre-wrap'
+            temp.style.wordWrap = 'break-word'
+            temp.style.font = window.getComputedStyle(textarea).font
+            temp.textContent = textBeforeCursor + '\n'
+            document.body.appendChild(temp)
+
+            const { lineHeight } = window.getComputedStyle(textarea)
+            // const textareaRect = textarea.getBoundingClientRect()
+            this.cursorPosition = {
+                top: temp.clientHeight - parseFloat(lineHeight) + textarea.offsetTop,
+                left: textarea.offsetLeft + 10
+            }
+
+            document.body.removeChild(temp)
+        },
+        handleScroll () {
+            this.scrollTop = this.$refs.codeEditor.scrollTop
+            if (this.showSuggestions) {
+                this.updateCursorPosition()
+            }
+        }
+    }
+}
+</script>
+
+<style scoped>
+        .code-editor {
+            position: relative;
+            color: black;
+            display: inline-block;
+        }
+        .code-input {
+            width: 100%;
+            font-family: monospace;
+            resize: none;
+            display: inline-block;
+            line-height: 15px;
+            margin-bottom: 0;
+            font-size: 13px;
+            border: 1px solid grey;
+            padding: 4.5px;
+            border-radius: 20px;
+        }
+        .suggestions-box {
+            position: absolute;
+            background: white;
+            border: 1px solid #ccc;
+            border-radius: 4px;
+            max-height: 150px;
+            overflow-y: auto;
+            z-index: 1000;
+            width: 200px;
+            box-shadow: 0 2px 10px rgba(0,0,0,0.1);
+        }
+        .suggestion-item {
+            cursor: pointer;
+            line-height: 20px;
+
+        }
+        .suggestion-item.selected {
+            background-color: #f0f0f0;
+        }
+    </style>
diff --git a/src/components/PlotSetup.vue b/src/components/PlotSetup.vue
index 727ff38..561d4b1 100644
--- a/src/components/PlotSetup.vue
+++ b/src/components/PlotSetup.vue
@@ -12,11 +12,11 @@
             <ul class="colorpicker plot-wrapper">
         <template v-if="state.expressions.length">
           <li v-for="(field, index) in state.expressions" :key="'field'+index" class="field plotsetup">
-              <input
+              <expression-editor
                 v-model.lazy="field.name"
                 v-debounce="1000"
-                class="plotname"
-              >
+                :suggestions="completionOptions"
+              />
                         <select v-model.number="field.axis">
               <option v-for="axis in state.allAxis" :key="'axisnumber'+axis" :value="axis">{{ axis }}</option>
                         </select>
@@ -82,9 +82,19 @@
 <script>
 import { store } from './Globals.js'
 import debounce from 'v-debounce'
+import ExpressionEditor from './ExpressionEditor.vue'
+
+const additionalCompletionItems = [
+    'mag_heading_df(',
+    'mag_heading(',
+    'named(NAMED_VALUE_FLOAT, name)'
+]
 
 export default {
     name: 'PlotSetup',
+    components: {
+        ExpressionEditor
+    },
     directives: {
         debounce
     },
@@ -94,6 +104,15 @@ export default {
             name: ''
         }
     },
+    computed: {
+        completionOptions () {
+            const messageOptions = Object.keys(this.state.messageTypes).flatMap(key => {
+                const fields = this.state.messageTypes[key].expressions.map(field => `${key}.${field}`)
+                return [key, ...fields]
+            })
+            return [...additionalCompletionItems, ...messageOptions]
+        }
+    },
     methods: {
         createNewExpression () {
             this.state.plotOn = true
@@ -147,7 +166,7 @@ export default {
 <style>
 /* MAIN */
     .plot-wrapper {
-        max-height: 160px;
+        min-height: 160px;
         overflow: hidden;
         overflow-y: scroll;
     }
@@ -194,7 +213,7 @@ export default {
         line-height: 15px;
         margin-bottom: 0;
         font-size: 13px;
-        width: 59%;
+        width: 100%;
         border: 1px solid grey;
         padding: 4.5px;
         border-radius: 20px;