Free Computing Tools
12 free online computing tools covering IP subnetting, number-base conversion, Base64 and URL encoding, password generation, GPA and grades, sample sizing and network transfer math. Every tool runs entirely in your browser — your data never leaves your device.
About computing tools
These tools cover the day-to-day maths of computing: working out what subnet a CIDR block represents, converting between number bases, encoding text for URLs or API payloads, estimating how long a download will take, or converting college grades into a GPA. Every tool performs its work locally in JavaScript — no data is transmitted to a server.
Encoders, generators and converters are useful for both everyday tasks and for teaching: for example, the binary converter shows the positional weight of each bit, and the IP subnet calculator displays the network address, broadcast, first and last usable host, and total hosts per subnet so you can trace exactly how the answer was produced.
Networking & Number Bases
IP subnetting, binary, decimal and network capacity tools.
IP Subnet Calculator
Compute network, broadcast, host range and mask from CIDR notation.
Binary to Decimal Converter
Convert binary values to decimal, octal and hexadecimal.
Decimal to Binary Converter
Convert decimal integers into binary representation with bit breakdown.
Bandwidth Calculator
Estimate bandwidth needs from concurrent users and usage patterns.
Download Time Calculator
Estimate download or upload time from file size and connection speed.
Encoding & Security
Text encoders, decoders and secure random password generation.
Academic & Statistical
GPA, grade tracking and sample size estimation.
GPA Calculator
Compute GPA on a 4.0 scale from course grades and credits.
Grade Calculator
Find the grade needed on a final exam to reach a target score.
Weighted Grade Calculator
Compute a weighted grade from category averages.
Sample Size Calculator
Compute required sample size for a survey or study.
Related Guides
Background reading for the maths behind these tools.
Computing Tool FAQs
The IP subnet calculator focuses on IPv4 CIDR blocks, which is the common case for home and office networks. IPv6 support is under consideration.
No. The password generator uses the browser's cryptographically secure random number generator (crypto.getRandomValues) and the result is displayed only on your device. Nothing is transmitted or stored.
GPA = Σ (grade points × credits) / Σ credits. The GPA calculator supports both the standard unweighted 4.0 scale and weighted scales that add bonus points for honours and AP courses.
Real-world throughput is lower than the nominal link speed due to protocol overhead, server limitations, network congestion and peak-hour throttling. The download time calculator gives a best-case estimate — expect actual times to be 10–30% longer.
Explore Other Categories
Related tools from other sections of Daily Calculator.