Tech calculators cover the sizing and budgeting questions that come up when running software: how much bandwidth a traffic level consumes, what an uptime promise allows in downtime minutes, what a cloud bill will look like, and whether a colour pair meets accessibility contrast rules.
9 calculators in this category
Network speeds are quoted in bits per second while file sizes are in bytes, a factor of eight that causes most bandwidth misestimates. On top of that, protocol overhead from TCP and TLS means usable throughput is meaningfully below the nominal link rate, so plan on roughly 85 to 90% of the headline figure for sustained transfers.
Storage carries its own ambiguity: drive manufacturers use decimal gigabytes of 1,000,000,000 bytes while operating systems often report binary gibibytes, which is why a 1 TB drive shows as about 931 GB.
An SLA percentage converts directly into an allowance of downtime. Three nines — 99.9% — permits about 8 hours 46 minutes a year, while 99.99% permits under an hour, and each additional nine multiplies the engineering cost of redundancy and on-call coverage. Quoting a figure you cannot fund is worse than quoting a modest one you can meet.
Rate limits work the other way: a limit expressed per minute has to be reconciled with burst traffic, so the practical question is whether your peak second exceeds the bucket size, not whether your average is under the cap.
Password strength is measured in entropy bits, calculated from the size of the character pool and the length. Length dominates: adding characters raises entropy far faster than adding symbol types to a short password, which is why long passphrases outperform short complex strings.
Colour contrast has a defined threshold rather than a matter of taste. WCAG 2.1 requires a contrast ratio of at least 4.5:1 for normal body text and 3:1 for large text, computed from the relative luminance of the two colours.
Headline connection speeds are in bits per second and exclude protocol overhead, and the far end of the transfer may be the bottleneck. Expect sustained throughput around 85 to 90% of the link rate at best, and divide by eight to convert to bytes.
They capture the main components — compute hours, storage volume and data egress — but real bills include support plans, request charges, cross-zone traffic and regional price differences. Treat an estimate as a floor and check the provider's current price list for your specific region.
99.9% is a common and achievable target for a single well-run service, allowing roughly nine hours of downtime a year including maintenance. Promising 99.99% requires redundancy across zones and staffed on-call, which is a very different cost base.
No. Entropy only measures resistance to guessing. A long unique password that has appeared in a breach is still compromised, so pair strength with a password manager, unique passwords per site, and two-factor authentication.