Surveillance capacity planning
Synology Surveillance Storage Calculator
Surveillance storage is a bitrate problem disguised as a resolution problem. Camera count, Mbps per stream, daily recording hours and retention days determine the recording payload. Codec, FPS and scene complexity influence bitrate, while RAID or SHR redundancy and free-space headroom determine how much raw disk capacity the NAS actually needs. This calculator keeps those layers separate so you can see the assumptions.
Quick answer
Use configured Mbps, not a resolution-only guess
Take the recording bitrate from the camera or Surveillance Station stream profile whenever possible. Multiply by camera count, recording hours and retention days, then add operational headroom. If recording is event-only, use a conservative activity percentage until measured site data is available.
Live Amazon products
Hardware and licenses relevant to this surveillance decision
This Sprint 9G catalogue tracks the Synology NAS, DVA appliances, cameras, license packs and selected Reolink examples used by these pages. Surveillance hard-drive cards are read from Cloudzat Storage Price Intelligence in read-only mode. Product cards support planning but never override Synology's live compatibility list, NVR Selector, license rules or camera firmware requirements.
Technical decision
Storage sizing should include failure and growth margin
Do not purchase drives to match the exact theoretical recording payload. The pool needs redundancy, file-system/operational headroom, retention rotation space and enough growth margin for bitrate increases, added cameras or longer retention.
Interactive surveillance tool
Synology Surveillance Storage Calculator
Use this as a planning aid. It applies the inputs you provide, but final camera limits, compatibility, licensing, package behavior and cloud plan details must be checked against Synology's current documentation and the exact hardware/firmware in use.
Deployment checklist
Four checks before a surveillance rollout
Prove the camera path
Verify the exact model, firmware and protocol in Synology Camera Support before buying or rolling out a large fleet.
Calculate licenses
Count actual device channels, multi-lens streams and special devices, then subtract only the licenses included with the chosen recorder.
Size by bitrate
Use configured Mbps, recording hours and retention days. Resolution alone is not a reliable surveillance-storage number.
Test recovery
After setup or upgrade, verify new recordings, playback, notifications, remote access and the procedure for retrieving critical footage.
Bitrate is the core input
Configured megabits per second translate directly into how many bytes a stream writes over time. Read the actual camera profile instead of using a generic 4K or 5MP assumption when accuracy matters.
Bitrate is the core input: Read the actual camera profile instead of using a generic 4K or 5MP assumption when accuracy matters. Configured megabits per second translate directly into how many bytes a stream writes over time.
Camera count scales storage linearly
Ten cameras at the same bitrate produce roughly ten times the recording data of one camera over the same period. Calculate each camera class separately when a deployment mixes entrances, parking areas and low-bitrate interior cameras.
Camera count scales storage linearly: Calculate each camera class separately when a deployment mixes entrances, parking areas and low-bitrate interior cameras. Ten cameras at the same bitrate produce roughly ten times the recording data of one camera over the same period.
Recording hours can reduce or explode capacity
Twenty-four-hour recording uses three times the daily payload of an eight-hour schedule at the same bitrate. Model the real operating schedule and retain continuous recording only where the evidence requirement justifies it.
Recording hours can reduce or explode capacity: Model the real operating schedule and retain continuous recording only where the evidence requirement justifies it. Twenty-four-hour recording uses three times the daily payload of an eight-hour schedule at the same bitrate.
Event recording needs a realistic activity factor
Motion/event recording can save large amounts of capacity, but busy scenes may record far more than expected. Start conservatively and replace the estimate with measured event-recording percentages after the system has run for several weeks.
Event recording needs a realistic activity factor: Start conservatively and replace the estimate with measured event-recording percentages after the system has run for several weeks. Motion/event recording can save large amounts of capacity, but busy scenes may record far more than expected.
Retention days are a policy decision
Thirty, ninety and 365-day retention targets create radically different storage requirements and may be driven by regulation or business policy. Agree on the retention objective before selecting drives so storage cost does not silently determine evidence policy.
Retention days are a policy decision: Agree on the retention objective before selecting drives so storage cost does not silently determine evidence policy. Thirty, ninety and 365-day retention targets create radically different storage requirements and may be driven by regulation or business policy.
Codec changes bitrate efficiency
H.265 can reduce bandwidth at comparable quality relative to H.264 in many camera configurations, but device and client compatibility still matters. Test playback and export on operator devices before using a codec change solely to save storage.
Codec changes bitrate efficiency: Test playback and export on operator devices before using a codec change solely to save storage. H.265 can reduce bandwidth at comparable quality relative to H.264 in many camera configurations, but device and client compatibility still matters.
Frame rate changes evidence and capacity
Higher FPS can improve motion detail while increasing bitrate requirements, especially when quality targets stay constant. Choose frame rate based on the scene and identification need rather than using the camera maximum everywhere.
Frame rate changes evidence and capacity: Choose frame rate based on the scene and identification need rather than using the camera maximum everywhere. Higher FPS can improve motion detail while increasing bitrate requirements, especially when quality targets stay constant.
Headroom protects recording operations
A pool planned to run at almost 100 percent capacity can behave poorly and leaves no room for temporary growth or policy changes. Keep a deliberate free-space margin above the calculated retention payload and monitor it over time.
Headroom protects recording operations: Keep a deliberate free-space margin above the calculated retention payload and monitor it over time. A pool planned to run at almost 100 percent capacity can behave poorly and leaves no room for temporary growth or policy changes.
RAID and SHR consume raw disk capacity
Redundancy protects availability but reduces usable capacity compared with the sum printed on drive labels. Calculate usable pool capacity separately and confirm it still exceeds the recording payload plus headroom.
RAID and SHR consume raw disk capacity: Calculate usable pool capacity separately and confirm it still exceeds the recording payload plus headroom. Redundancy protects availability but reduces usable capacity compared with the sum printed on drive labels.
Drive workload suitability matters
Surveillance recording creates sustained writes and frequent retention rotation, which differs from ordinary desktop storage use. Prefer drives rated for continuous NAS/surveillance workloads and verify the exact model against Synology compatibility guidance.
Drive workload suitability matters: Prefer drives rated for continuous NAS/surveillance workloads and verify the exact model against Synology compatibility guidance. Surveillance recording creates sustained writes and frequent retention rotation, which differs from ordinary desktop storage use.
Bandwidth and storage are linked
The same aggregate camera bitrate that fills disks also crosses the network into the recorder. Use the calculator’s aggregate Mbps output to sanity-check switch and NAS link capacity as well as storage.
Bandwidth and storage are linked: Use the calculator’s aggregate Mbps output to sanity-check switch and NAS link capacity as well as storage. The same aggregate camera bitrate that fills disks also crosses the network into the recorder.
Recalculate after real-world measurement
Camera defaults, scene complexity and event activity often change after commissioning. Review actual daily storage growth after one week and one month, then adjust retention thresholds before the pool becomes constrained.
Recalculate after real-world measurement: Review actual daily storage growth after one week and one month, then adjust retention thresholds before the pool becomes constrained. Camera defaults, scene complexity and event activity often change after commissioning.
Questions people ask
Synology surveillance storage questions
How do I calculate camera storage?
Multiply aggregate camera bitrate by recording time and retention days, convert bits to bytes, then add headroom and account for RAID/SHR usable capacity.
How much storage does a 4K camera need?
There is no single 4K figure because codec, FPS, quality and configured bitrate vary significantly between cameras and scenes.
Does H.265 save storage?
It often lowers required bitrate for similar visual quality, but the actual saving depends on encoder settings and end-to-end compatibility.
How much headroom should I leave?
Leave a deliberate operational margin above the retention payload; the calculator uses a planning margin rather than sizing to 100 percent fullness.
Does RAID count as extra storage?
No. Redundancy consumes raw disk capacity, so usable space is lower than the sum of all drive labels.
Should I calculate event recording at zero when nothing moves?
No. Use a conservative expected activity percentage until you have measured real recording duty cycle.
Does FPS affect storage?
Yes, because higher frame rates can require higher bitrate for comparable image quality and motion detail.
Why calculate network Mbps too?
Every recorded stream must reach the NAS, so aggregate camera bitrate is also a network-ingress planning value.
Can I use desktop hard drives?
For continuous surveillance, use drives suited to sustained NAS/surveillance workloads and confirm current Synology compatibility for the exact drive.
When should I recalculate capacity?
Recalculate when cameras, bitrate, codec, FPS, recording hours or retention policies change and compare estimates with actual daily storage growth.
Official references and methodology
Verify the exact camera, recorder, package build and licensing state
The calculator uses decimal storage units and the entered recording bitrate. It estimates recording payload, adds a planning headroom margin, and shows aggregate network bitrate. RAID/SHR usable capacity remains a separate design step because drive sizes and layout change the result.
- Synology NVR Selector
- Synology Surveillance Station specifications
- Synology DS425+ product page
- Synology DS925+ product page
- Synology DS1525+ product page
- Synology DS1825+ product page
As an Amazon Associate, Cloudzat may earn from qualifying purchases. Prices, camera firmware, product availability, license rules, Surveillance Station behavior and cloud-service plans can change. Verify the exact Synology model, camera support entry, package release notes and current service terms before purchasing hardware or changing a production surveillance system.