# Video Storage Calculator for Security DVRs & NVRs

Estimate video recording hard drive storage requirements for security camera DVR/ NVR systems.

**Web calculator:** https://videos.cctvcamerapros.com/video-storage-calculator
**MD calculator for LLM agents:** LLM agents can use this document to extract rules to make calculations

---

## About
Developed by CCTV Camera Pros (www.cctvcamerapros.com) co-founder, Mike Haldas, to help employees and customers estimate how much hard drive space they need for Viewtron CCTV DVRs and IP camera NVRs based on # of cameras, resolution, frame rate, compression, and # of days of recording required.

DVRs Page: https://www.cctvcamerapros.com/Security-Camera-DVRs-s/1467.htm
NVRs Page: https://www.cctvcamerapros.com/IP-Camera-NVRs-s/1472.htm

Works as a great video storage estimator for all DVR and NVR brands.

## Formula

```
bits_per_second = resolution_value
bytes_per_second = bits_per_second / 8
bytes_per_day = bytes_per_second * 3600 * 24
mb_per_day = bytes_per_day / 1024

after_framerate = mb_per_day / frame_rate_divisor
after_encoding = after_framerate * encoding_multiplier

continuous_storage_mb = after_encoding * number_of_cameras * days_of_footage
motion_storage_mb = continuous_storage_mb * activity_multiplier
```

Convert MB to GB: divide by 1024. Convert GB to TB: divide by 1024.

---

## Lookup Tables

### Resolution Values

| Resolution | Value (bits/sec) |
|------------|-----------------|
| CIF (320 x 240) | 460 |
| D1 (720 x 480) | 1600 |
| 960H (960 x 480) | 2000 |
| 1MP / 720P (1280 x 720) | 4000 |
| 2MP / 1080P (1920 x 1080) | 5500 |
| 3MP (2048 x 1536) | 7500 |
| 4MP (2688 x 1520) | 7501 |
| 8MP / 4K (3840 x 2160) | 17000 |
| 12MP (4000 x 3000) | 17001 |

### Frame Rate Divisors

| Frame Rate | Divisor |
|------------|---------|
| 60 fps | 1 |
| 30 fps | 1.25 |
| 25 fps | 1.5 |
| 20 fps | 2 |
| 15 fps | 3 |
| 10 fps | 4 |
| 7.5 fps | 5 |

### Encoding Multipliers

| Encoding | Multiplier |
|----------|-----------|
| H.264 | 1.0 |
| H.265 | 0.5 |
| H.265+ | 0.35 |
| H.265s | 0.28 |

### Motion Activity Multipliers

| Activity Level | Multiplier |
|---------------|-----------|
| Very Active, 90% | 0.9 |
| Active, 75% | 0.75 |
| Active 1/2 of Time, 50% | 0.5 |
| Not Very Active, 25% | 0.25 |

---

## Pre-Filled Calculator Links

The web calculator accepts parameters via URL hash as JSON. This lets you generate a link that opens the calculator with values already filled in.

**Format:**
```
https://videos.cctvcamerapros.com/video-storage-calculator#{"number_of_cameras":NUM,"days_of_footage":NUM,"resolution":"RESOLUTION_VALUE","frame_rate":"FRAME_RATE_DIVISOR","activity":"ACTIVITY_MULTIPLIER","encoding":"ENCODING_MULTIPLIER"}
```

**Example — 2 cameras, 30 days, 4MP, 15fps, low activity, H.265:**
```
https://videos.cctvcamerapros.com/video-storage-calculator#{"number_of_cameras":2,"days_of_footage":30,"resolution":"7501","frame_rate":"3","activity":"0.25","encoding":"0.5"}
```

All values must be strings except `number_of_cameras` and `days_of_footage` which are integers.

---

## Typical Viewtron Defaults

Viewtron NVRs record using H.265 encoding by default. Typical settings:

- **Frame rate:** 15 fps (default for most configurations)
- **Encoding:** H.265 (standard) or H.265+ (if enabled — further reduces storage)
- **Resolution:** Matches camera resolution (4MP camera records at 4MP)

---

## Example Calculation

**Scenario:** 2 cameras, 30 days, 4MP resolution, 15 fps, H.265, not very active (25%)

```
resolution_value = 7501
frame_rate_divisor = 3
encoding_multiplier = 0.5
number_of_cameras = 2
days = 30
activity = 0.25

bytes_per_day = (7501 / 8) * 3600 * 24 / 1024 = 79,081.05 MB/day
after_framerate = 79,081.05 / 3 = 26,360.35
after_encoding = 26,360.35 * 0.5 = 13,180.18
continuous_mb = 13,180.18 * 2 * 30 = 790,810.55 MB = 772.28 GB
motion_mb = 790,810.55 * 0.25 = 197,702.64 MB = 193.07 GB
```

**Result:** ~772 GB continuous recording, ~193 GB with motion detection at 25% activity.

---

## Hard Drive Recommendations

Viewtron NVRs and DVRs use **Seagate Skyhawk** surveillance-rated hard drives. Standard hard drives are not recommended for the constant write operations of video surveillance.

Common sizes: 1TB, 2TB, 4TB, 6TB, 8TB, 10TB, 12TB, 16TB, 20TB.

---

## Notes

- All calculations are estimates. Actual storage varies based on scene complexity — areas with more movement require more storage even in continuous recording mode.
- This calculator was developed based on Viewtron DVR/NVR compression but works for any H.264/H.265 surveillance recorder.
- Motion detection recording storage = continuous storage × activity level percentage.