# CCTV Storage Estimator

> Calculate hard drive size needed based on camera count, resolution, FPS, and retention days

**Category:** Dev
**Keywords:** cctv, storage, camera, surveillance, nvr, dvr, hard drive, hdd, bandwidth, security camera, video recording, h264, h265, retention, ip camera
**URL:** https://complete.tools/cctv-storage-estimator

## How it calculates

**Core Formula:**

```
Storage per Camera per Day (GB) = Bitrate (Mbps) x 86,400 / 8 / 1024 x (Recording % / 100)
```

**Where:**

- **Bitrate** is determined by resolution and codec at a base of 15 FPS, then scaled linearly for the selected frame rate
- **86,400** is the number of seconds in a day (3600 x 24)
- **Dividing by 8** converts megabits to megabytes
- **Dividing by 1024** converts megabytes to gigabytes
- **Recording %** is 100% for continuous recording, or the motion-activity percentage for motion-triggered recording

**Base Bitrate Table (at 15 FPS):**

| Resolution | H.264 | H.265 |
|-----------|-------|-------|
| 720p | 2 Mbps | 1 Mbps |
| 1080p | 4 Mbps | 2 Mbps |
| 2K / 4MP | 6 Mbps | 3 Mbps |
| 5MP | 8 Mbps | 4 Mbps |
| 4K / 8MP | 12 Mbps | 6 Mbps |

**FPS Scaling:** Bitrate scales proportionally. For example, 1080p H.264 at 30 FPS = 4 Mbps x (30/15) = 8 Mbps.

**Total Storage:** Multiply the per-camera daily figure by the number of cameras and the retention period in days.

**Recommended HDD:** The calculator rounds up to the next standard hard drive size (1, 2, 4, 6, 8, 10, 12, 14, 16, 18, or 20 TB) so you can purchase an off-the-shelf drive that fits your requirements.

## Who should use this

- **Security Installers and Integrators**: Size NVR/DVR storage accurately for client proposals and avoid costly change orders
- **IT Administrators**: Plan network infrastructure and storage procurement for office or campus surveillance systems
- **Homeowners**: Determine whether a basic 1 TB drive is sufficient or if a larger capacity is needed for a home security setup
- **Property Managers**: Calculate storage for multi-building complexes with dozens of cameras and long retention requirements
- **Retail Store Owners**: Ensure enough footage is retained for loss prevention investigations, often requiring 30-90 days
- **Warehouse and Logistics Managers**: Plan storage for high-camera-count environments where 4K resolution may be needed for detail

## How to use

1. Enter the number of cameras in your surveillance system
2. Select the camera resolution (720p, 1080p, 2K, 4MP, 5MP, or 4K/8MP)
3. Choose the frame rate your cameras will record at (common values are 15 or 30 FPS)
4. Select the video codec (H.265 uses roughly half the storage of H.264)
5. Choose between continuous recording or motion-triggered recording
6. If using motion-triggered mode, adjust the motion activity slider to reflect how busy your camera locations are
7. Enter the number of days you need to retain footage
8. Click "Calculate Storage" to see your results including recommended HDD size, per-camera daily usage, total storage, and network bandwidth requirements

## FAQs

**
**Q:** What is the difference between H.264 and H.265?**


**A:** H.265 (also called HEVC) is a newer compression standard that delivers the same video quality as H.264 at roughly half the bitrate. This means H.265 cuts your storage requirements in half compared to H.264. Most modern IP cameras and NVRs support H.265, making it the recommended choice for new installations.

**
**Q:** How much storage does a single 1080p camera use per day?**


**A:** At 15 FPS with H.264 encoding and continuous recording, a single 1080p camera uses approximately 42 GB per day. With H.265 encoding, that drops to about 21 GB per day. At 30 FPS, those figures double.

**
**Q:** Should I add extra storage beyond the calculated amount?**


**A:** Yes, it is good practice to add 10-20% overhead. Hard drives lose some capacity to filesystem formatting, and your NVR or DVR operating system needs space as well. The calculator recommends the next standard drive size up, which typically provides this buffer.

**
**Q:** What frame rate should I use for surveillance?**


**A:** For most security applications, 15 FPS provides smooth enough video to capture events clearly. Higher frame rates like 25 or 30 FPS are useful for fast-moving environments (traffic monitoring, sports facilities) but double the storage and bandwidth requirements. Some users drop to 5-10 FPS for less critical cameras to save space.

**
**Q:** How does motion-triggered recording reduce storage?**


**A:** Instead of recording 24 hours a day, the camera only writes to disk when motion is detected. In a typical quiet area (like a back hallway), motion may only occur 10-20% of the time, reducing storage by 80-90%. Busy areas like lobbies might see 40-70% activity. Set the motion percentage to match the expected activity level at each camera location.

**
**Q:** Can I use multiple smaller drives instead of one large drive?**


**A:** Yes. Many NVR systems support multiple drive bays with RAID configurations. For example, instead of one 16 TB drive, you could use two 8 TB drives in RAID 1 for redundancy, or four 8 TB drives in RAID 5 for both capacity and fault tolerance. Keep in mind that RAID configurations reduce usable capacity.

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*Generated from [complete.tools/cctv-storage-estimator](https://complete.tools/cctv-storage-estimator)*