Tech & Engineering

Cloud & Networking Calculators

Subnets, bandwidth, SLAs, storage and capacity planning. Free calculators with formulas and worked examples.

Web and hosting

Hosting Bandwidth CalculatorEstimate how much data your website transfers each month and how much bandwidth you need at peak, so you can pick a hosting…

Bandwidth and transfer

Data Transfer Time CalculatorWork out how long a transfer will take for a given size and connection speed.Data Rate Converter (Mbps, MB/s, Gbps)Convert a data rate between bits-per-second and bytes-per-second units.Bandwidth Needed CalculatorConvert monthly data volume into the line speed you need.

Reliability

SLA Uptime and Downtime CalculatorSee how much downtime a given SLA actually allows.Composite SLA Calculator (Serial and Parallel)Combine the availability of up to three components to see the overall result.MTBF and Availability CalculatorCombine MTBF and MTTR to find steady-state availability.SLO Error Budget Calculator (Downtime and Burn Rate)Enter the SLO, the window and your traffic and errors so far.

Telecom traffic

Erlang B CalculatorHow many calls will be blocked when traffic meets a fixed number of lines?VoIP Bandwidth CalculatorWork out how much bandwidth simultaneous voice calls need.

Network performance

Network Latency Calculator (Fibre Distance)How much latency does distance add to a network path?Bandwidth-Delay Product CalculatorFind how much data is in flight on a link, and the TCP window needed to fill it.TCP Throughput CalculatorSee what limits a TCP connection: the window, or packet loss.Page Load Time Calculator (Size, Bandwidth, Latency)Enter the page weight, connection speed and latency.

Storage

RAID Capacity CalculatorFind out how much usable space your drives give you under each RAID level.Storage Unit Converter (GB vs GiB)Convert storage sizes between decimal and binary units.CCTV and Video Storage CalculatorWork out how much storage your video recordings need.SSD Lifespan CalculatorConvert a TBW endurance rating into years of use.

Data centre

PUE Calculator (Data Centre Efficiency)Measure how efficiently a data centre turns power into computing.

Capacity planning

Server Capacity Planning CalculatorSize a fleet for peak traffic with headroom and redundancy.Call Center Staffing Calculator (Erlang C)Enter calls per hour, average handle time, agents and your service-level target time.Little's Law Calculator (Concurrency, Throughput, Latency)Choose what to find and enter the other two values.Kubernetes Node Calculator (Nodes for Your Pods)Enter the pods, their resource requests and the node size.

Cloud cost

Cloud Cost EstimatorEnter your provider's prices to estimate monthly compute, storage and transfer costs.Reserved vs On-Demand Savings CalculatorIs a reserved or committed-use discount worth it for your usage?

Wireless

dBm to Watts ConverterConvert dBm to mW and W, or mW to dBm.Free-Space Path Loss CalculatorHow much signal strength does a wireless link lose over distance?Wireless Link Budget CalculatorCheck whether a radio link has enough margin to work.

Security

Password Entropy and Cracking Time CalculatorSee how hard a randomly generated password is to guess.

Cloud costs

Cloud Storage Cost Calculator (Object Storage)Enter how much you store, your request counts and egress, with your provider's prices.

About these calculators

Planning tools for people who run networks and cloud systems: IP subnetting, data transfer time, uptime and downtime from SLA percentages, storage and throughput. Results are theoretical figures; real networks have overhead and variation.

Each calculator explains its formula, includes a worked example and lists its sources. Read how we check them on our editorial policy page, or browse all calculators.

More in Tech & Engineering

Electronics & EngineeringIP & Domain ToolsRF Wireless 4G & 5GTelecom Power & Passive InfrastructureAI & Computing

Please note: TheCalcTools gives general estimates for information and education. It is not financial, medical, legal or tax advice, and results should be checked before you make a decision. See our disclaimer and about page.