Linux & Unix Calculators
File systems, storage, memory, CPU, processes, permissions, security and system administration.
160 of 160 available now
File System
File Size CalculatorConvert file sizes between bytes, KB, MB, GB and TB with binary or decimal units.Directory Size CalculatorEstimate total directory size from file counts and average file sizes.Disk Usage CalculatorCalculate used, free and total disk space percentages for a Linux filesystem.Filesystem Utilization CalculatorDetermine filesystem capacity utilization and headroom before hitting full disk alerts.Inode Usage CalculatorCalculate inode consumption and remaining inode capacity on an ext4 or xfs filesystem.Block Size CalculatorCalculate the number of disk blocks required to store a file given the filesystem block size.Filesystem Overhead CalculatorEstimate metadata and journaling overhead a filesystem subtracts from raw partition capacity.Mount Point Capacity CalculatorCalculate available capacity across multiple mount points sharing an underlying volume.Disk Growth EstimatorProject when a disk volume will run out of space based on its current growth rate.Partition Size PlannerPlan partition sizes for root, home, var and swap based on total disk capacity.Swap Size CalculatorRecommend swap partition or swap file size based on installed RAM and workload type.Filesystem Resize CalculatorCalculate new usable capacity after growing or shrinking a filesystem or partition.Filesystem Fragmentation CalculatorEstimate filesystem fragmentation percentage from free extent counts and file counts.Hard Link Count CalculatorTrack hard link counts and their effect on inode reference counting and deletion.Symbolic Link Path CalculatorResolve relative and absolute symbolic link target paths across directory levels.File Compression Ratio CalculatorCalculate compression ratio and space savings between original and compressed file sizes.Backup Size EstimatorEstimate full and incremental backup sizes based on data volume and change rate.Restore Time CalculatorEstimate how long a backup restore will take based on data size and transfer throughput.Archive Size CalculatorEstimate tar or zip archive output size from source file sizes and compression method.File Count EstimatorEstimate the number of files a directory tree will contain based on depth and fan-out.
Storage
LVM PV Size CalculatorCalculate LVM physical volume size and metadata overhead for a given block device.LVM VG Capacity CalculatorCalculate total volume group capacity from combined physical volume extents.LVM LV Size CalculatorCalculate logical volume size allocation from available volume group extents.LVM Snapshot Size CalculatorSize an LVM snapshot volume based on expected change rate and snapshot lifetime.RAID 0 Capacity CalculatorCalculate total usable capacity and performance of a RAID 0 striped array.RAID 1 Capacity CalculatorCalculate usable capacity of a RAID 1 mirrored array from disk count and size.RAID 5 Capacity CalculatorCalculate usable capacity of a RAID 5 array accounting for single-disk parity.RAID 6 Capacity CalculatorCalculate usable capacity of a RAID 6 array accounting for dual-disk parity.RAID 10 Capacity CalculatorCalculate usable capacity of a RAID 10 striped-mirror array from disk count and size.RAID Performance CalculatorEstimate combined read and write IOPS across a RAID array based on level and disk count.Disk IOPS CalculatorCalculate achievable disk IOPS from rotational speed, seek time and queue depth.Disk Throughput CalculatorCalculate sequential read/write throughput in MB/s from block size and IOPS.SSD Lifetime CalculatorEstimate SSD lifespan from TBW rating, drive capacity and daily write volume.HDD Failure Probability CalculatorEstimate annual hard drive failure probability from AFR and fleet size.Storage Expansion CalculatorCalculate additional disks or capacity needed to reach a target storage size.SAN Capacity CalculatorCalculate usable SAN capacity after RAID overhead, thin provisioning and reserved space.NAS Capacity CalculatorCalculate usable NAS capacity after RAID redundancy and filesystem overhead.Storage Growth ForecastForecast future storage needs from historical growth rate and planning horizon.Disk Queue Length CalculatorCalculate average disk queue length from IOPS and service time using queuing theory.Filesystem Cache CalculatorEstimate page cache size needed to cache a working set of files in RAM.
Memory
RAM Usage CalculatorCalculate used, free and cached RAM percentages from free command output values.Memory Utilization CalculatorCalculate overall memory utilization percentage across physical RAM and swap.Swap Utilization CalculatorCalculate swap space usage percentage and estimate performance impact of swapping.Page Cache CalculatorCalculate the portion of RAM used as page cache and its effect on available memory.Buffer Cache CalculatorEstimate buffer cache size used for block device I/O buffering on Linux systems.Shared Memory CalculatorCalculate System V or POSIX shared memory segment size requirements for applications.HugePages CalculatorCalculate the number of HugePages needed to back a given amount of application memory.Kernel Memory CalculatorEstimate kernel memory footprint including slab allocations and kernel structures.Memory Leak EstimatorEstimate time until out-of-memory based on observed process memory leak rate.OOM Killer Threshold CalculatorCalculate the memory threshold at which the Linux OOM killer is likely to trigger.NUMA Memory PlannerPlan memory allocation across NUMA nodes to minimize remote memory access latency.Virtual Memory CalculatorCalculate virtual address space size and mapping requirements for a process.Page Table Size CalculatorCalculate page table memory overhead based on page size and mapped address space.Memory Fragmentation CalculatorEstimate memory fragmentation percentage from free memory chunk size distribution.Process Memory CalculatorCalculate total memory footprint of a process from RSS, shared and private memory.RSS CalculatorCalculate a process's Resident Set Size and its share of total physical memory.VSZ CalculatorCalculate a process's Virtual Size including mapped, reserved and unused address space.Heap Size CalculatorCalculate recommended heap size for a process based on workload and object allocation rate.Stack Size CalculatorCalculate thread stack size requirements and total stack memory for multi-threaded processes.Memory Growth ForecastForecast future memory consumption from historical usage trend and growth rate.
CPU
CPU Utilization CalculatorCalculate CPU utilization percentage from user, system and idle time measurements.Load Average CalculatorInterpret 1, 5 and 15-minute load averages relative to available CPU cores.CPU Core Requirement CalculatorCalculate the number of CPU cores needed to handle a target workload and concurrency.CPU Frequency CalculatorCalculate effective CPU clock frequency accounting for turbo boost and throttling.CPU Bottleneck CalculatorIdentify whether CPU is the limiting resource by comparing load, wait and I/O metrics.CPU Scheduling CalculatorCalculate process scheduling time slices under the Linux CFS scheduler.Context Switch CalculatorEstimate context switch overhead and its impact on effective CPU throughput.Interrupt Rate CalculatorCalculate hardware interrupt rate per second and its CPU overhead impact.System Load CalculatorCalculate overall system load combining CPU, I/O wait and runnable process counts.Thread Count CalculatorCalculate optimal thread count for a workload based on core count and I/O wait ratio.Process Count CalculatorCalculate maximum concurrent processes supportable given CPU and memory constraints.CPU Affinity CalculatorCalculate CPU affinity masks for pinning processes to specific cores with taskset.Hyperthreading Efficiency CalculatorEstimate effective performance gain from hyperthreading versus physical core count.Core Utilization CalculatorCalculate per-core CPU utilization from mpstat metrics across a multi-core system.Idle CPU Percentage CalculatorCalculate idle CPU percentage and headroom available for additional workload.CPU Wait Time CalculatorCalculate I/O wait time percentage and its effect on overall CPU responsiveness.CPU Burst Time CalculatorCalculate CPU burst time and turnaround time for scheduling algorithm analysis.CPU Capacity PlannerPlan CPU capacity needs for future growth based on current utilization trends.CPU Power Consumption CalculatorEstimate CPU power draw and energy cost based on TDP and utilization level.CPU Thermal CalculatorEstimate CPU operating temperature and thermal throttling risk under sustained load.
Processes
PID Range CalculatorCalculate PID exhaustion risk from pid_max and current process creation rate.Zombie Process RatioCalculate the ratio of zombie processes to total processes on a running system.Fork Rate CalculatorCalculate process fork rate per second and its impact on system overhead.Process Lifetime CalculatorCalculate average process lifetime and turnover rate from start and end timestamps.Cron Schedule CalculatorParse and explain a cron expression, showing the resulting execution schedule.Cron Next Run CalculatorCalculate the next several run times for a given cron expression and timezone.at Job Scheduler CalculatorCalculate the exact execution time for a one-off job scheduled with the at command.systemd Service Dependency CalculatorCalculate systemd unit startup order and dependency chain resolution time.Service Restart Delay CalculatorCalculate cumulative restart delay for a systemd service using exponential backoff.Daemon Count CalculatorCalculate the number of background daemons running and their aggregate resource usage.Open File Descriptor CalculatorCalculate open file descriptor usage against system and per-process ulimit thresholds.ulimit CalculatorCalculate recommended ulimit values for file descriptors, processes and memory.Thread Pool Size CalculatorCalculate optimal thread pool size for a service based on request rate and latency.Job Queue Size CalculatorCalculate required job queue depth to absorb burst traffic without dropping jobs.Background Process CalculatorCalculate combined resource footprint of background processes running via nohup or &.Foreground Process PlannerPlan foreground process resource allocation to avoid contention with background jobs.Process Priority nice CalculatorCalculate effective process priority from nice value and scheduling class.Renice Value CalculatorCalculate the renice adjustment needed to shift a running process's CPU scheduling priority.Signal Delivery Time CalculatorEstimate signal delivery latency to a target process under varying system load.System Uptime CalculatorCalculate system uptime duration and availability percentage from boot timestamp.
Networking
Socket Count CalculatorCalculate maximum concurrent socket connections supportable by system file descriptor limits.TCP Connection CalculatorCalculate maximum concurrent TCP connections a server can handle given port and memory limits.UDP Port CalculatorCalculate available UDP port range and usable ports after reserved and ephemeral ranges.Network Buffer Size CalculatorCalculate optimal socket send/receive buffer sizes based on bandwidth and latency.MTU CalculatorCalculate maximum transmission unit and payload size after protocol header overhead.MSS CalculatorCalculate maximum segment size from MTU by subtracting TCP/IP header overhead.TCP Window Size CalculatorCalculate optimal TCP window size from bandwidth-delay product for maximum throughput.Bandwidth Utilization CalculatorCalculate network bandwidth utilization percentage against interface link capacity.Packet Rate CalculatorCalculate packets-per-second rate and its CPU load impact on network interrupt handling.NIC Throughput CalculatorCalculate achievable throughput of a network interface card given link speed and overhead.Interface Queue CalculatorCalculate network interface queue length needed to avoid packet drops under burst load.Bonding Capacity CalculatorCalculate aggregate bandwidth capacity of a bonded network interface across multiple NICs.Bridge Interface CalculatorCalculate throughput and MAC table capacity for a Linux bridge interface.VLAN Interface CalculatorCalculate available VLAN IDs and subinterface count for 802.1Q tagged networking.Routing Table Size CalculatorCalculate routing table memory footprint from route count and kernel FIB entry size.ARP Cache CalculatorCalculate ARP cache size and expiration behavior based on neighbor table thresholds.DNS Cache Size CalculatorCalculate DNS resolver cache size needed to serve a given query rate and TTL distribution.Hostname Resolution TimeEstimate hostname resolution latency across DNS, /etc/hosts and cache lookup layers.Connection Tracking CalculatorCalculate conntrack table size needed for a firewall or NAT gateway's connection load.Socket Buffer CalculatorCalculate total kernel memory consumed by socket send and receive buffers system-wide.
Security
File Permission CalculatorConvert Linux file permissions between octal, symbolic and chmod notation instantly.Octal Permission CalculatorConvert numeric octal permission codes like 755 or 644 into readable rwx notation.Symbolic Permission CalculatorConvert symbolic permission strings like rwxr-xr-- into octal chmod values.SUID CalculatorCalculate the resulting permission bits and security implications of setting the SUID bit.SGID CalculatorCalculate the resulting permission bits and behavior of setting the SGID bit on files or directories.Sticky Bit CalculatorCalculate the resulting permission bits of setting the sticky bit on shared directories.ACL Permission CalculatorCalculate effective access permissions when POSIX ACLs override standard file mode bits.SELinux Context CalculatorDecode SELinux security context labels into user, role, type and sensitivity components.AppArmor Profile CalculatorEstimate AppArmor profile rule coverage and enforcement mode impact on an application.SSH Key Length CalculatorCompare SSH key algorithm and bit-length strength across RSA, ECDSA and Ed25519.SSH Connection Capacity CalculatorCalculate maximum concurrent SSH sessions supportable under sshd MaxSessions and MaxStartups.SSH Session Timeout CalculatorCalculate SSH idle session timeout from ClientAliveInterval and ClientAliveCountMax settings.Password Expiry CalculatorCalculate password expiration date from chage aging policy settings like PASS_MAX_DAYS.Password Entropy CalculatorCalculate password entropy in bits from character set size and password length.Hash Speed CalculatorEstimate hashing throughput and brute-force crack time for a given hash algorithm.SHA Checksum CalculatorCalculate SHA-1, SHA-256 and SHA-512 checksum length and verification time for a file.MD5 Checksum CalculatorCalculate MD5 checksum verification time for files based on size and hashing throughput.Certificate Expiry CalculatorCalculate days remaining until an SSL/TLS certificate expires and renewal deadline.Log Rotation Size CalculatorCalculate total disk space consumed by rotated log files based on logrotate retention policy.Audit Log Growth CalculatorEstimate auditd log growth rate and storage needs based on audit rule verbosity.
System Administration
Boot Time CalculatorBreak down system boot time across firmware, kernel and systemd unit startup phases.Kernel Parameter CalculatorCalculate recommended sysctl kernel parameter values for a given workload profile.Kernel Thread CalculatorCalculate the number of kernel threads spawned per CPU core for common kernel subsystems.Module Dependency CalculatorCalculate kernel module load order and dependency depth from modinfo dependency chains.Package Dependency CalculatorCalculate total download size and install order for a package and its dependency tree.Repository Mirror CalculatorCalculate storage and bandwidth needed to host a local mirror of a package repository.YUM DNF Cache CalculatorCalculate disk space consumed by the YUM or DNF package manager metadata and RPM cache.APT Cache CalculatorCalculate disk space consumed by the APT package cache and downloaded .deb archives.Package Size CalculatorEstimate installed size versus download size for a software package and its dependencies.Update Time EstimatorEstimate total time to download and install a batch of system package updates.Patch Window CalculatorCalculate the maintenance window duration needed to patch a fleet of servers safely.Reboot Duration CalculatorEstimate total server downtime from shutdown, POST, kernel boot and service startup phases.Service Availability CalculatorCalculate service uptime percentage and allowed downtime budget for an SLA target.Log Growth CalculatorEstimate application log directory growth rate and days until disk capacity is reached.Syslog Storage CalculatorCalculate storage required for centralized syslog collection from a fleet of hosts.Journalctl Disk Usage CalculatorCalculate systemd journal disk usage against SystemMaxUse and runtime journal limits.Kernel Log Size CalculatorCalculate dmesg kernel ring buffer size and message retention capacity.System Capacity PlannerPlan overall CPU, memory and storage capacity needed to support projected system growth.Server Consolidation CalculatorCalculate how many physical servers can be consolidated into virtual machines or containers.Linux Server Health Score CalculatorCalculate an overall server health score from CPU, memory, disk and service uptime metrics.