Every device connected to the internet is assigned an IP address, but not all IP addresses work the same way. The two main types — static and dynamic — serve different purposes and come with distinct advantages. Understanding the difference is essential for anyone managing a network, running a server, or simply trying to understand how their internet connection works.
What Is a Dynamic IP Address?
A dynamic IP address is one that your Internet Service Provider (ISP) assigns to your device automatically, and it can change over time. Most home internet connections use dynamic IP addresses. Your ISP maintains a pool of available addresses and assigns one to your router each time it connects. When your router restarts or your DHCP lease expires, you may receive a different IP.
You can check your current IP address at any time by visiting WheresThatIP.com. If you check on different days, you may notice the address has changed — that means you have a dynamic IP.
How Dynamic IP Assignment Works
Dynamic IPs are assigned using the Dynamic Host Configuration Protocol (DHCP). Here is the process:
- Your device connects to the network and sends a DHCP Discover message
- The DHCP server (usually your router or ISP) responds with an available IP address
- Your device accepts the address and uses it for a set period (the "lease time")
- When the lease expires, the process repeats and you may get a new address
What Is a Static IP Address?
A static IP address is a fixed address that never changes. It is manually configured or permanently assigned by your ISP. Static IPs are commonly used for servers, business networks, and remote access configurations where a consistent address is required.
If you need to set up a static IP on your device, see our guide on how to set up a static IP address.
Key Differences at a Glance
| Feature | Static IP | Dynamic IP |
|---|---|---|
| Changes over time | No — stays the same | Yes — can change periodically |
| Cost | Usually extra ($5-15/month from ISP) | Included with service |
| Setup | Requires manual configuration or ISP request | Automatic via DHCP |
| Best for | Servers, VPN, remote access, hosting | Home browsing, general use |
| Security | Easier to target (address never changes) | Harder to target (address rotates) |
| DNS compatibility | Works directly with DNS records | Requires dynamic DNS (DDNS) services |
| Availability | Limited — must be requested | Default for most ISPs |
When You Need a Static IP
Static IP addresses are essential in several scenarios:
- Web hosting — Running a web server or email server requires a consistent address so DNS records point to the right place. Use our DNS lookup tool to verify your server's records.
- Remote access — Connecting to your home or office network remotely is simpler when the IP does not change
- VPN servers — Hosting your own VPN endpoint requires a fixed address for clients to connect to
- Security cameras and IoT — Devices that need to be accessed remotely benefit from a static address
- IP whitelisting — Many APIs and services require you to whitelist specific IPs for access. Learn more in our IP whitelisting guide.
When a Dynamic IP Is Fine
For most people, a dynamic IP address works perfectly well:
- General web browsing and streaming
- Email (using services like Gmail, Outlook)
- Online gaming — Modern games handle IP changes seamlessly
- Privacy — A changing IP makes long-term tracking slightly harder
Security Considerations
Both types have security trade-offs:
Static IP Risks
- Since the address never changes, attackers who discover it can target it persistently
- Easier to track and profile over time
- Requires more diligent firewall and security configuration
Dynamic IP Advantages
- Rotating addresses make sustained attacks harder
- Provides a basic level of obscurity (though not true privacy)
- If you want stronger privacy, consider using a VPN service regardless of your IP type
To learn what someone can do with your IP, read our guide on what someone can do with your IP address.
How to Tell If You Have a Static or Dynamic IP
- Visit WheresThatIP.com and note your IP address
- Restart your router and wait for it to reconnect
- Check your IP again
- If it changed, you have a dynamic IP. If it stayed the same, you likely have a static IP (or your DHCP lease has not expired yet — try again after 24 hours)
How to Get a Static IP
If you decide you need a static IP:
- Contact your ISP — Most ISPs offer static IPs as an add-on for $5-15/month
- Use a business plan — Business internet plans often include one or more static IPs
- Use Dynamic DNS — If you cannot get a static IP, services like No-IP or DynDNS can map a hostname to your changing IP, giving you a stable way to reach your network
Frequently Asked Questions
Can I set a static IP on my local network?
Yes. You can assign a static private IP to any device on your local network through your router's DHCP reservation settings or the device's network configuration. This is different from having a static public IP from your ISP. See our static IP setup guide for step-by-step instructions.
Does a static IP make my internet faster?
No. Your internet speed is determined by your ISP plan, not your IP type. However, static IPs can reduce minor reconnection delays that sometimes occur when DHCP leases renew.
Is a static IP safer than a dynamic IP?
Neither is inherently safer. Static IPs are easier to target but also easier to whitelist and monitor. Dynamic IPs offer some obscurity but are not a substitute for proper security measures like firewalls, VPNs, and keeping software updated.