DNS "propagation" is the time it takes for caches around the internet to drop an old DNS answer and fetch the new one. A record change usually shows up within the record's TTL, often minutes to a few hours. A nameserver change can take up to 24–48 hours, because the parent zone (.com, .ca) publishes nameserver records with long cache times. You can shorten the wait by lowering TTLs in advance, and you can check the result with dig, nslookup and online checkers.
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What actually happens
When someone opens your website, their device asks a DNS resolver (usually run by their internet provider, or a public one such as Google's 8.8.8.8 or Cloudflare's 1.1.1.1) for the address of your domain. The resolver asks the authoritative nameservers for your domain and keeps the answer in its cache for as long as the record's TTL (time to live) allows, measured in seconds. Until that time runs out, it keeps giving the old answer to everyone who asks.
Nothing is pushed out to the world when you edit a record. Each resolver refreshes on its own schedule, which is why one person sees the new site while a colleague in another city still sees the old one.
Typical waiting times
- Changing an A, CNAME, MX or TXT record: up to the old TTL of that record. With a TTL of 3600, expect up to an hour; with 86400, up to a day.
- Changing nameservers: the .com registry publishes nameserver records with a TTL of 172800 seconds (48 hours), so some resolvers can keep the old nameservers for up to two days. Other endings use their own values.
- A record that did not exist before: resolvers that recently got a "no such record" answer cache that too, for a period set in your zone's SOA record.
How to plan and check a DNS change in 7 steps
Step 1. Write down the current records
Before any change, export or screenshot the full DNS zone: A, AAAA, CNAME, MX, TXT (SPF, DKIM, DMARC, verification codes), SRV and CAA records. Most outages after a move come from records that nobody copied, often email records or a verification TXT record.
Step 2. Lower the TTL a day ahead
Set the TTL of the records you are going to change to 300 seconds (five minutes), and do it at least one old-TTL period before the change. If the old TTL was 86400, lower it a full day ahead, so every cache picks up the short TTL before you switch.
Step 3. Make the change at the right place
Edit the records where the domain's DNS is actually hosted. That is the provider whose nameservers are listed for the domain, which may be your registrar, your host or a service such as Cloudflare. Editing records in a panel the domain does not use changes nothing. If your registrar hosts DNS, as Namecheap domains do by default, the records are in the registrar's dashboard.
Step 4. Check the authoritative answer first
Ask your domain's own nameservers directly, which skips all caches:
dig example.ca NS +short shows the nameservers, and dig @ns1.yourdnsprovider.com example.ca A +short shows what they answer. On Windows, nslookup example.ca ns1.yourdnsprovider.com does the same. If the authoritative answer is wrong, waiting will not help; fix the record.
Prefer to hand it off? MMIX sets up domain, hosting, email and DNS for you — since 2012.
Fill in a short briefStep 5. Check public resolvers and other regions
Query the large public resolvers: dig @8.8.8.8 example.ca A +short and dig @1.1.1.1 example.ca A +short. Then use an online checker such as DNSChecker, which asks resolvers in many countries at once. Google and Cloudflare also offer pages to request a cache refresh for a domain on their public resolvers: Google Public DNS cache flush and Cloudflare 1.1.1.1 purge cache.
Step 6. Clear your own device's cache
Your computer and browser keep their own DNS cache. On Windows run ipconfig /flushdns. On macOS run sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder. In Chrome, open chrome://net-internals/#dns and clear the host cache. A phone on mobile data (with Wi-Fi off) is a quick second opinion, since it uses a different resolver.
Step 7. Raise the TTL back and watch email
Once the new records answer everywhere, set the TTL back to a normal value such as 3600. For a day or two, keep the old server running and watch email delivery, because some mail servers retry against cached records. Send test messages to and from Gmail and Outlook addresses and check the headers for SPF, DKIM and DMARC results.
What to check: common DNS mistakes
- Changing nameservers to a new provider before copying the zone. The new provider starts with an empty or partial zone, and email stops. Copy every record first.
- Two SPF records. A domain must have a single SPF TXT record; merge the entries into one.
- Deleting the old hosting too early. Keep it for at least the longest TTL involved, plus a margin.
- A CNAME on the root domain. Standard DNS does not allow a CNAME at the root alongside other records. Use an A record or your provider's flattening feature.
- Testing only from the office. Your office resolver may cache the old answer for hours while the rest of the country sees the new one.
Moving to a new host? Our hosting guide and VPS guide cover the steps around the DNS switch.
FAQ
How long does DNS propagation take?
A changed record is usually visible everywhere within its previous TTL, often minutes to a few hours. A nameserver change can take up to 24–48 hours, because the registry publishes nameserver records with long cache times.
Can I speed up DNS propagation?
You cannot force every resolver in the world to refresh. You can lower the TTL a day before the change, request a cache refresh on Google and Cloudflare public resolvers, and flush the cache on your own devices.
Why do I see the new website but my client sees the old one?
You and your client use different DNS resolvers, and each one keeps its cached answer until the TTL ends. Your client's resolver will switch to the new answer when its cache expires.
What TTL should I use?
For records that rarely change, 3600 seconds (one hour) is a common choice. Lower the TTL to 300 seconds a day before a planned change and raise it again once the change is complete.
How do I check if my DNS change worked?
Query your domain's authoritative nameservers with dig or nslookup to confirm the new value, then check public resolvers such as 8.8.8.8 and 1.1.1.1 and an online checker that queries several countries.
Does DNS propagation affect email?
Yes. When you change MX records, some senders keep delivering to the old mail server until their cached record expires. Keep the old mailboxes running for a few days after the switch and check them for late messages.
Prefer to hand it off? MMIX sets up domain, hosting, email and DNS for you — since 2012. Tell us what you have now and what you need, and we will reply with a plan.
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