Security & Surveillance
Security Camera Cable Run Calculator
Total cable length for a camera install
Updated July 12, 2026 · Live
What this tool does
Works out the total cable length for a camera install from the camera count, average run to the recorder and a slack allowance — length only, never gauge.
Enter the camera count, the average run to the recorder and a slack allowance; the calculator returns the total cable length.
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Formula Used
Works out the total cable length for a camera install from the camera count, average run to the recorder and a slack allowance — length only, never gauge. It runs entirely in your browser and shows the working, so you can check every step against your own figures.
How the security camera cable run calculator works
The total is the number of cameras times the average run to the recorder, plus a slack percentage for routing around obstacles, service loops and the drops down to each camera. The result is the length of cable to buy. The tool also checks the average run against the roughly 100 m reliable limit for standard PoE.
What you enter
Enter the camera count, the average run to the recorder and a slack allowance; the calculator returns the total cable length. Every field is editable, and the result recalculates the moment you change a value.
Reading the result
Buy a full drum rather than exact metres — joins in surveillance cable are best avoided. If any run approaches 100 m, plan a mid-span switch or a PoE extender rather than pushing the limit.
Safe by design
This tool plans coverage, storage and cable length. It never specifies conductor gauge or PoE circuit sizing — the electrical side is a qualified installer’s responsibility.
Assumptions and limits
This gives length only — never the conductor gauge or the PoE power budget, which are electrical calculations for a qualified installer. Real runs vary; measure the longest ones directly rather than trusting an average for a critical camera.
Using it with the rest of BuildMetricLab
This calculator is one step in planning the job. Pair it with the related tools in this category and across BuildMetricLab to go from a single figure to a full costed plan — a sizing figure feeds a cost estimate, a cost estimate feeds a project budget, and each result carries straight into the next tool. Every BuildMetricLab tool runs entirely in your browser — no sign-up, nothing sent to a server, and the formula is shown on the page so the maths can be audited.
Sources & methodology
Works out the total cable length for a camera install from the camera count, average run to the recorder and a slack allowance — length only, never gauge. Every result is calculated from the values you enter, all inputs are editable, and no time-sensitive prices or rates are embedded.
Frequently asked questions
How much cable should I buy?
This tool totals the runs plus slack. Buy a full spool rather than exact feet — surveillance cable is best run in one unbroken length.
What is the PoE distance limit?
Standard PoE over twisted-pair copper is reliable to about 328 feet (100 m). Beyond that, use a mid-span switch or a PoE extender.
Does this tell me the cable gauge?
No — deliberately. Conductor gauge and PoE power budgets are electrical calculations for a qualified installer.
Why add slack?
Cable rarely runs straight — routing around obstacles, service loops at each end and the drop to the camera all add length.
Spotted something off?
Calculations or display — let us know.