When a website has problems, "clear your cache" is the standard advice. But which cache? Many people don't realize there are multiple distinct caches that affect web browsing — and clearing the wrong one won't fix the problem. DNS cache and browser cache are fundamentally different systems that fail in different ways. Here's exactly what each one does and when to clear it.
Clear Browser Cache for Any Site Instantly
The Clear Cache extension handles browser cache — one click to clear stored content for any site. No navigation through Chrome settings needed.
Add to Chrome — FreeDNS Cache: The Phone Book
Every time you type a domain name like google.com into your browser, something has to look up the IP address (142.250.80.46) where that website actually lives. This lookup happens via the Domain Name System (DNS) — essentially a distributed phone book for the internet.
DNS lookups add latency (typically 20–100ms) to every new connection. To avoid repeating this lookup on every request, your computer caches the result. This is DNS cache.
Where DNS Cache Lives
- Operating system DNS cache: Your Windows, Mac, or Linux OS caches DNS results from all applications
- Chrome's internal DNS cache: Chrome maintains its own DNS cache independent of the OS
- Your router/modem: Most home routers also cache DNS results
- Your ISP's DNS servers: Internet service providers cache DNS at their infrastructure level
DNS Cache Time-to-Live (TTL)
Each DNS record has a Time-to-Live (TTL) value set by the domain owner — typically 300 seconds (5 minutes) to 86400 seconds (24 hours). Your DNS cache respects this TTL and refreshes automatically. The problem arises when a site changes its IP address and your cached TTL hasn't expired yet — you keep going to the old server.
Browser Cache: The Content Store
Browser cache stores the actual files that make up websites: HTML pages, CSS stylesheets, JavaScript files, images, fonts, and other static resources. The purpose is to avoid re-downloading unchanged files on every visit — a website's logo, for example, doesn't change daily and shouldn't be downloaded fresh every time you visit.
What Browser Cache Stores
- HTML documents (page structure)
- CSS files (styling and layout)
- JavaScript files (interactive behavior)
- Images (JPEG, PNG, WebP, SVG)
- Fonts (WOFF, WOFF2)
- Video and audio files served from the site
- Service worker scripts (for offline functionality)
Browser Cache Does NOT Store
- IP addresses (that's DNS)
- Passwords (stored in password manager)
- Login sessions (stored in cookies)
- Your browsing history (stored separately)
Side-by-Side Comparison
| Property | DNS Cache | Browser Cache |
|---|---|---|
| What it stores | Domain → IP address mappings | Website files (HTML, CSS, images, JS) |
| Where it lives | OS level, Chrome internal, router | Your local disk (Chrome profile folder) |
| Purpose | Faster domain resolution | Faster page loading |
| Problems when stale | Can't reach site, wrong server, SSL errors | Outdated content, broken CSS/JS |
| Controlled by | Domain TTL settings | HTTP cache headers (Cache-Control) |
| Clear via Chrome | chrome://net-internals/#dns | Settings → Clear browsing data |
| Clear via OS | ipconfig /flushdns (Windows) | Not applicable (Chrome-managed) |
| Affects all sites? | Yes | Yes (unless site-specific clear) |
| Affects login? | No | No (cookies handle login) |
When to Clear DNS Cache
Signs You Have a DNS Cache Problem
- "ERR_NAME_NOT_RESOLVED" or "This site can't be reached" for a site that works on other devices
- You recently changed your
hostsfile and the change isn't taking effect - A website recently migrated to a new server and you're being sent to the old (possibly offline) server
- SSL certificate errors that reference the wrong domain or IP
- Accessing local development environments that conflict with cached public DNS entries
How to Clear Chrome's Internal DNS Cache
How to Clear the OS-Level DNS Cache
ipconfig /flushdnsYou'll see "Successfully flushed the DNS Resolver Cache."
sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponderEnter your admin password when prompted. No confirmation message appears — this is normal.
sudo systemd-resolve --flush-cachesOr for older systems using nscd:
sudo service nscd restart
When to Clear Browser Cache
Signs You Have a Browser Cache Problem
- A website shows content that you know has been updated
- CSS styling looks broken or inconsistent with how the site looks on another device
- JavaScript functionality is broken on a site that was recently updated
- Fonts or icons don't render correctly
- A site you control shows old content after you've made changes
- An image placeholder appears instead of the actual image
How to Clear Browser Cache in Chrome
Clear Site Cache Without Touching DNS
The Clear Cache extension precisely clears browser cache for a single site — the content layer — without affecting DNS resolution, cookies, or other sites.
Install Clear Cache — FreeChrome Also Has a DNS-over-HTTPS Cache
Chrome has added its own DNS-over-HTTPS (DoH) functionality, which creates another DNS cache layer at the browser level — separate from both Chrome's traditional DNS cache and the OS DNS cache. If you use Chrome's secure DNS feature, this cache is also managed through chrome://net-internals/#dns.
For most users, the distinction doesn't matter — clearing Chrome's DNS cache via chrome://net-internals/#dns handles both traditional and DoH cached entries.
The Complete Clearing Workflow
If a site isn't working and you're not sure which cache is the problem, clear both in sequence:
- Clear Chrome's DNS cache:
chrome://net-internals/#dns→ Clear host cache - Clear OS DNS cache:
ipconfig /flushdns(Windows) or the macOS equivalent - Clear browser cache: Use Clear Cache extension or Ctrl+Shift+Delete
- Hard refresh: Ctrl+Shift+R
- Test the site in an Incognito window (rules out extensions interfering)
Frequently Asked Questions
What's the difference between DNS cache and browser cache?
DNS cache stores domain-to-IP mappings — it remembers that "google.com" points to a specific IP so lookups are fast. Browser cache stores actual website content: HTML, CSS, images, JavaScript. DNS cache affects whether your computer can find a website's server. Browser cache affects what content is shown once the server is found.
How do I clear DNS cache in Chrome?
Go to chrome://net-internals/#dns in Chrome's address bar and click "Clear host cache." For the OS-level DNS cache on Windows: open Command Prompt and run ipconfig /flushdns. On Mac: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder in Terminal.
When should I clear DNS cache vs browser cache?
Clear DNS cache when you're getting "site can't be reached" errors or when a site recently moved to a new server. Clear browser cache when the site loads but shows outdated content, broken CSS, or wrong images. When in doubt about which is causing the problem, clear both.
Can stale DNS cause browser errors?
Yes. Stale DNS can cause "ERR_NAME_NOT_RESOLVED," "This site can't be reached," or SSL certificate errors if the old IP address's certificate doesn't match the domain. After a site migrates to a new server, flushing your DNS cache immediately applies the new IP address rather than waiting for TTL expiration.
Does clearing browser cache also clear DNS cache?
No. Chrome's Clear Browsing Data (Ctrl+Shift+Delete) clears browser cache files but does not flush the DNS cache. DNS cache must be cleared separately through chrome://net-internals/#dns or the OS-level ipconfig /flushdns command.
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