Practice with calibrated drills
Drill one skill, mix a level, or let the app pick your weak spots. Every wrong answer names the mistake behind it.
Binary and decimal
NewConvert any octet between binary and decimal. Stage 1: Foundations.
5 questions across foundations and core subnetting. Once you have answers, this targets your weak spots.
Pick from four options. Good while you learn the method.
Take your time. Blitz always has its own clock.
Per level round. Skill drills are 8.
Levels
Mixed rounds. Each level covers a range of prefixes and a set of skills.
Novice
Octet 4
Binary, prefix to mask and back, host counts, block sizes and network/broadcast in the last octet.
Intermediate
Octet 4
The 60-second method, sizing for hosts, wildcard masks and on-link vs gateway routing.
Advanced
Octet 3
Third-octet subnets, sizing for subnet counts, overlap checks and longest-prefix match.
Master
Octet 2
Second-octet subnets, VLSM design, route summarization, prefix splitting and troubleshooting.
60-second blitz
60sUp to 10 mixed questions against one clock, in your chosen answer mode. When time runs out, the round ends and only the questions you saw are scored.
Skill drills
8 questions on one skill. Mastered means 8+ answers at 80% or better.
- Binary and decimalNew
Convert any octet between binary and decimal.
Not tried yet0% - Prefix to maskNew
Write the dotted mask for any prefix.
Not tried yet0% - Mask to prefixNew
Read a dotted mask as a prefix length.
Not tried yet0% - Host countNew
Count usable hosts in any subnet.
Not tried yet0% - Block sizeNew
Find the magic number for any prefix.
Not tried yet0%
Tip: in Choose mode answer with 1–4; in Type mode press Enter to check. Continue with Enter.