Bolt performance

React Re-rendering Causing Performance Issues - Slow Interactions

Your app feels sluggish when interacting. Typing in inputs lags, clicking buttons is unresponsive. React is re-rendering too much.

Frame rate drops during interactions or when state updates happen.

Error Messages You Might See

Component re-rendering 100+ times per keystroke Frame rate dropping to 10FPS JavaScript long tasks blocking main thread Interaction to Next Paint > 200ms
Component re-rendering 100+ times per keystrokeFrame rate dropping to 10FPSJavaScript long tasks blocking main threadInteraction to Next Paint > 200ms

Common Causes

  1. Parent component re-rendering, causing all children to re-render unnecessarily
  2. Heavy computations happening during render
  3. State updates too frequently or on every keystroke without debounce
  4. Missing useMemo or useCallback, causing child components to re-render
  5. Large lists rendering all items instead of virtualizing

How to Fix It

Use React DevTools Profiler to identify slow components

Memoize expensive computations: useMemo(() => expensiveCalc(data), [data])

Memoize callbacks: useCallback(fn, deps) to prevent child re-renders

Use React.memo for components that receive same props

Debounce input: useDebounce(value, 300) for search/filters

Virtualize long lists: react-window or react-virtualized

Real developers can help you.

Pratik Pratik SWE with 15+ years of experience building and maintaining web apps and extensive BE infrastructure MFox MFox Full-stack professional senior engineer (15+years). Extensive experience in software development, qa, and IP networking. Jaime Orts-Caroff Jaime Orts-Caroff I'm a Senior Android developer, open to work in various fields Kingsley Omage Kingsley Omage Fullstack software engineer passionate about AI Agents, blockchain, LLMs. Daniel Vázquez Daniel Vázquez Software Engineer with over 10 years of experience on Startups, Government, big tech industry & consulting. Mehdi Ben Haddou Mehdi Ben Haddou - Founder of Chessigma (1M+ users) & many small projects - ex Founding Engineer @Uplane (YC F25) - ex Software Engineer @Amazon and @Booking.com Matthew Jordan Matthew Jordan I've been working at a large software company named Kainos for 2 years, and mainly specialise in Platform Engineering. I regularly enjoy working on software products outside of work, and I'm a huge fan of game development using Unity. I personally enjoy Python & C# in my spare time, but I also specialise in multiple different platform-related technologies from my day job. Meïr Ankri Meïr Ankri Full-stack developer specializing in React / Next.js / Node.js with 6+ years of experience. I've worked across various sectors including automotive (Reezocar/Société Générale), healthcare (Medical Link SaaS), and e-commerce (Glasman). I build web apps end-to-end, from architecture to production, with a focus on scalability, performance, and code quality. I also mentor junior developers and contribute to technical decisions and code reviews. Costea Adrian Costea Adrian Embedded Engineer specilizing in perception systems. Latest project was a adas camera calibration system. rayush33 rayush33 JavaScript (React.js, React Native, Node.js) Developer with demonstrated industry experience of 4+ years, actively looking for opportunities to hone my skills as well as help small-scale business owners with solutions to technical problems

You don't need to be technical. Just describe what's wrong and a verified developer will handle the rest.

Get Help

Frequently Asked Questions

How do I know if component is re-rendering too much?

React DevTools Profiler - record interaction, see render counts. Add console.log to component

Should I memoize everything?

No, adds overhead. Only memoize expensive calculations or passed-to-children functions

What's the difference between useMemo and useCallback?

useMemo caches computed value. useCallback caches function reference. Both prevent unnecessary re-renders of children

Related Bolt Issues

Can't fix it yourself?
Real developers can help.

You don't need to be technical. Just describe what's wrong and a verified developer will handle the rest.

Get Help