Free Tools for Small Business Cybersecurity
Section updated .
Four free tools for the small-business security decisions that come down to a calculation or a checklist: what an outage costs, how long a restore will take, how ready you are for ransomware, and what DMARC record to publish for your email domain. Each uses only what you enter, shows its method, runs in your browser and needs no sign-up. This is an independent publication.
Every tool page states its method in plain words and works through an example with clearly hypothetical numbers, so you can reach the same answer on paper if you prefer. Nothing you type leaves your browser, and nothing is stored.
The tools
Downtime Cost Calculator
Put a number on an outage from your own staff, revenue and recovery figures, with every step of the arithmetic shown.
Open the tool →Backup Restore Time Estimator
Turn data size and restore speed into hours, with bits and bytes handled for you and every step of the arithmetic shown.
Open the tool →Ransomware Readiness Self-Check
Twelve yes-or-no questions across backups, identity, email, patching and response, with the guide to read for each gap.
Open the tool →DMARC Record Builder
Build a valid DMARC TXT record and the exact DNS name to publish it at, with a staged plan from monitoring to reject.
Open the tool →How to use these well
Gather your own figures before you start — payroll cost per hour and sales per hour for the downtime calculator, a measured speed from a test restore for the estimator, an honest answer to each question in the readiness check, and the domain and mailbox you will use for DMARC reports. The boxes start empty on purpose: the grey text is an example only. Where a tool asks for a personal judgement, such as the share of productivity lost or the allowance for overhead, it is your choice and not a rule. For the reasoning behind the tools, see the recovery-time planning and SPF, DKIM and DMARC guides.
Frequently asked questions
Are these tools free?
Yes, all of them, with no sign-up. Each runs entirely in your browser, so nothing you enter is sent anywhere and nothing is stored after you close the page.
Do the tools know my costs, speeds or controls?
No, deliberately. Costs, restore speeds and the state of your controls differ between businesses, so you supply them from your own records and tests. The grey text in each box is a marked example only.
How accurate are the results?
They are estimates built from stated formulas, and each page shows the method in words so you can check the working. The tools use only what you enter, so figures from your own records and tests give far more useful answers than guesses.
Can a tool tell me whether my business is secure?
No. The readiness check is a self-assessment of twelve points and the other tools are calculators. None of them is an audit, a certification or a substitute for testing your own backups and controls.
Do they work offline?
Yes. The pages and the calculations are self-contained, so they keep working without a connection once the page has loaded.
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