> For the complete documentation index, see [llms.txt](https://hacking-notes.jord4n.pro/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hacking-notes.jord4n.pro/hacking-tools/calculators.md).

# Calculators

Practical calculator hub for subnetting, Linux permissions, and cron expressions using searchable GitBook tables and quick triage notes.

This section groups fast lookup calculators for common pentesting and administration tasks. Each page uses searchable GitBook tables, so you can type the value you need and jump directly to the result.

## Calculator Index

<table data-view="cards" data-full-width="false" data-search="true"><thead><tr><th></th><th></th><th></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><h3><i class="fa-network-wired" style="color:$primary;">:network-wired:</i></h3></td><td><h4>Subnetting Calculator</h4></td><td>Search CIDR ranges, subnet masks, wildcard masks, host counts, block size, and subnetting examples.</td><td><a href="/hacking-tools/calculators/subnetting-calculator.md">Subnetting Calculator</a></td></tr><tr><td><h3><i class="fa-key" style="color:$primary;">:key:</i></h3></td><td><h4>Linux Permissions Calculator</h4></td><td>Convert octal permissions to symbolic notation, review SUID/SGID/sticky bits, and identify privilege escalation impact.</td><td><a href="/privesc/permissions/linux-permissions-calculator.md">Linux Permissions Calculator</a></td></tr><tr><td><h3><i class="fa-clock" style="color:$primary;">:clock:</i></h3></td><td><h4>Cron Expression Calculator</h4></td><td>Search common cron expressions, read their human meaning, and review cron privilege escalation checks.</td><td><a href="/privesc/cron-jobs/cron-expression-calculator.md">Cron Expression Calculator</a></td></tr></tbody></table>

## Fast Usage

| Need                        | Search For                            |
| --------------------------- | ------------------------------------- |
| Network mask and host count | `/24`, `/27`, `/30`                   |
| Linux permission conversion | `755`, `644`, `4755`, `rwxr-xr-x`     |
| Cron schedule meaning       | `*/5 * * * *`, `0 0 * * *`, `@reboot` |


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# Agent Instructions
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