CCTV Storage Calculator 2026 — Free IP Camera HDD Size Tool

📹 Free Surveillance Tool — DoCrack.me

CCTV Storage Calculator 2026 — IP Camera HDD Size Tool

Calculate exactly how much hard drive space your IP camera system needs. Supports mixed camera groups, H.264/H.265/H.265+, RAID 0/1/5/6/10, and NVR recommendations. Free, no signup.

Resolutions

RAID types

2yr

Max retention

Free

No registration

How much storage does your CCTV system actually need?

Over-buying HDDs wastes budget. Under-buying means overwriting footage before incidents are reviewed. The right answer depends on camera count, resolution, codec, recording schedule, and retention period — and most online estimates get it wrong.

This calculator uses real-world bitrate values for each codec and resolution combination. Add multiple camera groups with different settings — useful for mixed deployments where entry cameras use 4K while perimeter cameras use 2MP with H.265+.

After calculating raw storage, the tool factors in your RAID type, OS overhead, and chosen HDD size to give you an exact drive count and NVR configuration recommendation.

⚠️ Always add 20–30% buffer above calculated values and verify with test recordings before final hardware procurement.

What this tool calculates

✓Total storage per camera group

✓H.264, H.265, H.265+ codec comparison

✓RAID 0, 1, 5, 6, 10 drive count

✓Exact number of HDDs needed

✓NVR model recommendations

✓Network bandwidth per group

✓Retention from 7 days to 2 years

✓Bitrate reference table + print report

docrack.me/cctv_storage_calculator.html

Key concepts explained

H.265+

Smart codec savings

Saves 50–70% storage vs H.265 in low-motion scenes. Compatible cameras and NVR must be from the same brand.

RAID 5 vs 6

Which to choose

RAID 6 for 8+ large drives — rebuilds take 24–72hrs and RAID 5 risks total loss on a second failure during that window.

Retention

How long to keep footage

30 days is standard for most businesses. Banks and casinos typically require 90 days. Some regulations require 1 year.

HDD Type

Surveillance-grade only

Use Seagate SkyHawk, WD Purple, or Toshiba S300. Desktop drives fail within 6–18 months under 24/7 write loads.

Common questions

▶ How accurate are these storage calculations?

Actual storage can vary ±20–40% depending on scene complexity — a busy street generates far more data than an empty corridor. Always add a 20–30% buffer and verify with test recordings from your actual cameras before final hardware procurement.

▶ What is H.265+ and how much storage does it save?

H.265+ (Dahua Smart Codec / Hikvision H.265 Pro) compresses static backgrounds aggressively while keeping full quality on moving objects. In low-motion environments it saves 50–70% vs standard H.265. In busy scenes savings drop to 20–35%. Requires matching cameras and NVR from the same brand.

▶ Should I use RAID 5 or RAID 6 for CCTV?

RAID 6 for arrays with 8+ large drives. With 8–16TB HDDs a RAID 5 rebuild takes 24–72 hours — a second failure during that window means total data loss. RAID 6 tolerates two simultaneous failures. For critical sites (banks, casinos), dual-recording to two separate servers is preferable over any RAID.

▶ NVR vs DVR — what is the storage difference?

DVRs connect to analog cameras via coax — storage is internal to the unit, typically 4–8 drives. NVRs connect to IP cameras over ethernet and can use internal drives or external NAS/storage servers, enabling hundreds of terabytes. VMS platforms like Dahua DSS Pro use dedicated storage server nodes separate from the management server.

▶ How much does motion recording reduce storage?

A busy retail entrance records 60–80% of the time (modest savings). A rarely-accessed server room may record only 5–15% of the time (massive savings). Use 20–40% motion activity for typical indoor environments, 40–60% for moderate outdoor scenes.