Best app for CCNA prep
This is up there with Jeremy’s IT Lab in terms of importance for CCNA studying. You can get as many VLSM repetitions as you want with this app. I can’t stop using it.
Free
About
Practice subnetting for IT certifications like CCNA and Network+. This offline tool offers randomized questions with verified calculations and multiple answer formats. Track your progress with session and total counters, and receive optional daily practice reminders.
✓Offline subnetting quizzes
✓Randomly generated questions
✓Multiple choice or written answers
✓Session and total progress tracking
✓Built-in block-size reference
✓Daily practice reminders
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What's New in Subnet Driller
1.2
August 20, 2026
Fixed: if your device region uses a comma as the decimal separator — Norwegian, German, French, Portuguese and many others — you could not type an IP address at all, because the number pad has no period key. Commas now become dots as you type. Regions that use non-Latin numerals (Arabic, Persian, Hindi) now work too. Thank you to the person who wrote in about this — please keep the reports coming.
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FAQ
What is Subnet Driller?
Subnet Driller is an offline application designed to help users practice subnetting calculations for IT certifications like CCNA and Network+. It features randomly generated questions and verified calculations.
Does Subnet Driller have ads?
No, Subnet Driller is completely ad-free. The app is designed to provide an uninterrupted learning experience without any advertisements.
What IT certifications does Subnet Driller support?
Subnet Driller is specifically designed for practice related to CCNA and Network+ certifications. It can also be useful for other networking certifications requiring subnetting knowledge.
How does Subnet Driller track progress?
The app includes SESSION and TOTAL counters to track your performance. It also provides a per-type accuracy breakdown, allowing you to see your strengths and weaknesses in different subnetting question types.
Can I use Subnet Driller offline?
Yes, Subnet Driller is fully offline. You do not need an internet connection to use the app, and it does not require any accounts or tracking.
What types of subnetting questions are available in Subnet Driller?
Subnet Driller offers five question types: network address, broadcast address, first usable host, last usable host, and usable host count. You can choose between multiple choice or written answers, or a mix of both.
How often is Subnet Driller updated?
The latest version of Subnet Driller was released on 2026-06-12, indicating recent development activity. The developer actively reads and replies to user feedback for potential improvements.
What is the learning methodology of Subnet Driller?
Subnet Driller focuses on repetition and speed using the 'magic number' or block-size method for subnetting calculations. This method is designed for efficient memorization and quick problem-solving.