Clean, useful
Slick design and super helpful for practicing subnetting. Nothing gets in the way.
Response from developer
Thanks!
Free
About
This offline calculator quickly determines IP network details like network address, host ranges, and broadcast addresses. It supports various input formats and provides advanced information, including binary views and IPv6 compatibility. Designed for network professionals and students, it offers a streamlined way to perform subnet calculations without an internet connection.
✓Offline subnet calculation
✓Supports CIDR, bare address, or subnet mask input
✓Calculates network, host, and broadcast addresses
✓Pastes directly from network device output
✓Provides wildcard mask and binary views
✓Handles /31 and /32 subnetting
✓IPv6 support
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What's New in Slash
2.1
June 12, 2026
- Settings now links to Subnet Driller, the practice app that split out of Slash - Small fixes
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FAQ
What is Slash used for?
Slash is an offline subnet calculator designed to quickly determine IP network details such as network address, host ranges, and broadcast addresses. It's useful for network engineers and students studying for certifications like CCNA and Network+.
Does Slash have ads?
No, Slash is completely ad-free. The app explicitly states it has no ads, tracking, or subscriptions, providing an uninterrupted user experience.
Is Slash free to use?
Yes, Slash is available for free. The app's monetization model is listed as free, with no in-app purchases or subscription fees required.
Can Slash be used offline?
Yes, Slash is fully offline. This means you can perform all subnet calculations without needing an internet connection, making it ideal for field work or areas with limited connectivity.
What kind of input does Slash accept?
Slash accepts a CIDR notation (e.g., 192.168.1.0/24), a bare IP address, or a subnet mask as input. It can also paste directly from Cisco IOS, ifconfig, or ipconfig output.
Does Slash support IPv6?
Yes, Slash includes support for IPv6 calculations when needed. It also offers light or dark themes and optional haptic feedback.
How accurate is the subnet math in Slash?
The subnet math in Slash is hand-verified for accuracy. The developer, a working network engineer, has ensured the core calculations are reliable for professional use.
What devices can I use Slash on?
Slash is supported on Mac, iPhone, and iPad devices. This cross-platform compatibility allows users to perform calculations on their preferred Apple devices.