Salesforce LWC Tips for Optimizing Performance

Why LWC Performance Matters

Salesforce Lightning Web Components (LWC) are designed to be lightweight and fast—but poor development practices can quickly bloat components, slow down rendering, and frustrate users. Whether you’re building a dashboard, data-entry form, or mobile interface, performance optimization is key.

In this guide, you’ll find 15 advanced LWC tips to boost speed, maintain UX fluidity, and make your Salesforce apps shine—even at scale.

---

1. Use lwc:if Over if:true={}

Why: It supports branching logic (if / elseif / else) and simplifies conditional UI rendering.

---

2. Reduce Re-Renders Using Object Spread

Instead of updating properties one-by-one, use object spread syntax to batch updates and trigger only one re-render.

jsCopyEditthis.user = { ...this.user, name: 'Alex', age: 30 };

---

3. Debounce Inputs to Minimize Apex Load

Avoid triggering Apex for every keystroke. Use lodash.debounce or custom functions.

---

4. Use @wire with cacheable=true

Prefer @wire over imperative calls for simple reads. This allows Salesforce to cache responses.

apexCopyEdit@AuraEnabled(cacheable=true)
public static List<Account> getAccounts() {
    return [SELECT Id, Name FROM Account];
}


jsCopyEdit@wire(getAccounts) accounts;

---

5. Lazy Load Scripts with loadScript

Only load resources like Chart.js or Moment.js when necessary.

jsCopyEditimport { loadScript } from 'lightning/platformResourceLoader';

loadChartJs() {
  if (!this.chartJsLoaded) {
    loadScript(this, chartJs).then(() => {
      this.chartJsLoaded = true;
      this.initChart();
    });
  }
}

---

6. Flatten Deeply Nested Components

Avoid nesting 3+ levels deep. Prefer slots or modular flat components for reuse and performance.

---

7. Use Lightning Data Service (LDS) for Standard CRUD

htmlCopyEdit<lightning-record-form
  object-api-name="Contact"
  record-id={recordId}
  layout-type="Compact"
  mode="view"
></lightning-record-form>

---

8. Cache DOM Selectors and Avoid Loops

jsCopyEditconnectedCallback() {
  this.searchInput = this.template.querySelector('.search-input');
}

Don’t call querySelector inside loops or frequent callbacks.

---

9. Use requestAnimationFrame() for DOM Animations

jsCopyEditrenderedCallback() {
  window.requestAnimationFrame(() => {
    this.renderChart();
  });
}

This helps browser batching and smooth UI updates.

---

10. Avoid Heavy Logic in renderedCallback

jsCopyEditrenderedCallback() {
  if (this.initialized) return;
  this.initialized = true;
  this.initializeData();
}

---

11. Use for:each with key for Lists

htmlCopyEdit<template for:each={contacts} for:item="contact">
  <p key={contact.Id}>{contact.Name}</p>
</template>

---

12. Break Large Components into Small, Testable Units

Split dashboards, wizards, and tables into small subcomponents. This reduces rendering cost and increases testability.

---

13. Use Computed Getters for Conditional Logic

jsCopyEditget showChart() {
  return this.hasData && !this.hasError;
}

htmlCopyEdit<template lwc:if={showChart}>
  <c-performance-chart data={chartData}></c-performance-chart>
</template>

---

14. Use Chrome DevTools + LWC Inspector

• LWC Inspector: Analyze component hierarchy, reactivity, and wire performance.
• DevTools: Track memory, network latency, and DOM rendering time.

---

15. Watch Salesforce Governor Limits

Limit Type	Threshold	Optimization Tip
SOQL Queries	100/query	Combine queries, use maps
Heap Size	6MB/12MB	Avoid massive JSON, large objects
CPU Time	10,000ms	Flatten loops, avoid nested calls
DML Statements	150/tx	Use upsert, bulk inserts

---

✅ Final Developer Checklist

• All lists use for:each + key
• lwc:if used instead of if:true
• DOM queries are cached
• Lazy loading via loadScript
• Debounced input handling
• No heavy logic in lifecycle methods