How to Check DHCP Lease Time on Windows, Linux, and macOS

On Windows, run ipconfig /all and find Lease Obtained and Lease Expires under the active DHCP adapter. Their difference gives the displayed lease interval; expiration minus the current time gives the remaining time. Linux and macOS expose similar information through their network tools.

Then compare the endpoint with the DHCP server's scope and lease record. ZDNS provides current and historical IP information, transaction logs, and address-pool visibility for that server-side check. One client's lease does not establish the setting received by every device.

Windows: Read the active adapter's lease

In Command Prompt, find the adapter connected to the network you are investigating. Check DHCP Enabled, DHCP Server, Lease Obtained, and Lease Expires. Ignore disconnected adapters and unrelated VPN or virtual interfaces.

For example, obtained at 09:00 and expiring at 17:00 shows an eight-hour interval. At 12:00, five hours remain. Record the adapter, address, server, and timestamps so the server-side lookup refers to the same lease.

Linux: Check the network manager in use

For an interface managed by NetworkManager, run:

Replace with the connected device, such as eth0. Inspect DHCP4 options for lease duration and server information when available. Output varies with the backend and version; missing lease details do not by themselves establish that the lease is infinite.

If timing information is absent, inspect the NetworkManager journal. For systems using systemd-networkd or another DHCP client, use that service's status and logs instead. A stale lease file or an interface's address lifetime may not represent the negotiated DHCP duration.

macOS: Inspect the accepted DHCP packet

Identify the active interface first; it is not always en0. Then run:

The command prints the accepted DHCP packet when available. Look for lease_time and server_identifier. Lease duration is expressed in seconds, sometimes displayed in hexadecimal: 0x7080 is 28,800 seconds, or eight hours. No output can mean DHCP is inactive on that interface or acquisition was unsuccessful.

Compare the client with the matching scope

Locate the server lease by IP address and client identifier or MAC address. Verify the scope, configured duration, relevant policy overrides, and time of the latest acknowledgment. Check the server that actually handled the request, especially in a redundant deployment.

• Configured duration: the policy currently set on the server.
• Granted duration: the value accepted in a particular DHCP exchange.
• Remaining time: the interval from now until expiration.

A policy change may not yet appear on an existing client. Confirm a later successful exchange before concluding that the new setting is ignored. Match clocks and time zones when comparing client timestamps and server logs.

Understand renewal without disrupting connectivity

For DHCPv4, default T1 and T2 are 50% and 87.5% of the lease when explicit values are absent. With an eight-hour lease, renewal normally starts around four hours and rebinding around seven. These events occur before expiration; a successful renewal can retain the same address.

Start with passive inspection. A release command discards the current configuration and can disconnect remote access. If a controlled test needs renewal, Windows supports ipconfig /renew; account for possible configuration changes and connectivity effects.

For an office client with an unexpected duration, compare its acknowledgment with the scope policy. For a guest subnet under address pressure, sample several clients and examine utilization. ZDNS address history and utilization reporting can help distinguish an individual lease observation from a wider capacity problem.

Use the packet exchange when values disagree

If client and server views remain inconsistent, inspect the relevant DHCPACK in a permitted capture. DHCPv4 option 51 carries lease time; options 58 and 59 carry renewal and rebinding timers when supplied. Match the client and server identifiers to avoid interpreting another endpoint's exchange.

Also check the resolver addresses delivered to the client when investigating DNS resolution. DHCP lease time and DNS TTL are separate values. DHCPv6 uses different lifetime fields and should be checked separately.

Once the received value is confirmed, use the recommended DHCP lease time guide to decide whether it fits the network. Record the interface, duration, server, scope, and exchange time before changing policy.