Free IT tools

RAID Calculator

Usable capacity, fault tolerance, IOPS, rebuild time and URE risk for every RAID level — including ZFS RAIDZ.

ZFS / RAIDZ Calculator

Size a ZFS pool properly: parity, ~3.2% slop, padding, multi-vdev pools and the 80% fill rule.

TB ↔ TiB Converter

Convert decimal TB to binary TiB (and GB↔GiB) and see why a 16 TB drive shows as 14.55 TiB.

IOPS ↔ MB/s Converter

Convert IOPS to throughput (MB/s) and GB/day at any block size.

DWPD / TBW Calculator

Convert SSD endurance between drive-writes-per-day and total-bytes-written.

Finder

Storage Solution Finder

Set capacity, IOPS, workload and budget for a workload-matched platform recommendation.

Lifecycle

Storage EOSL Checker

Look up end-of-service-life dates for storage arrays and plan refreshes or third-party maintenance.

Lifecycle

Server & Network EOSL Checker

Sourced end-of-service-life dates for HPE, Dell, Cisco, Lenovo & Juniper servers and switches — extend, refurbish or refresh.

UPS Sizing & Runtime Calculator

Build your IT load → recommended UPS kVA/kW, load current, heat output and a runtime estimate.

Watts ↔ Amps ↔ VA Calculator

Convert between watts, amps and volt-amps (single- and three-phase) with power factor.

Server Room Cooling Calculator

Turn an IT load into the cooling needed in BTU/hr and tons, with margin and N+1.

Password Strength Checker

Test how strong a password is and how long it would take to crack — 100% in your browser.

Generator

Business Password Generator

Generate up to 100 strong random passwords at once, with CSV export for IT admins.

Generator

Passphrase Generator

Strong, memorable "three random words" passphrases with adjustable length and separators.

Developer

Hash Generator

SHA-256, SHA-1, SHA-384 and SHA-512 hashes of any text, computed locally.

Developer

UUID Generator

Random version-4 UUIDs in bulk (up to 100) — copy one or all.

Assessment

Security Risk Assessment

Free Windows security audit: 17 categories, an A–F score and a remediation roadmap.

Security Header Checker

Grade a site’s HTTP security headers (HSTS, CSP, X-Frame-Options…) against the OWASP set, with fixes.

Comparison

Microsoft 365 Backup Comparison

Compare Veeam, AvePoint, Acronis, Commvault, Dropsuite and Druva side by side — filter by need and estimate cost per user.

Subnet Calculator

IPv4 subnet/CIDR: network, broadcast, host range, mask, wildcard, scope and a subnet splitter.

What Is My IP?

See your public IP, version, scope and reverse DNS — read from your connection, no trackers.

DNS Lookup

Resolve a domain to its IP and DNS records (A, AAAA, CNAME, MX, NS, TXT), live.

Planner

VLSM Calculator

Divide a network into right-sized subnets from your required host counts, largest-first.

CIDR Calculator

CIDR ↔ subnet mask ↔ address range ↔ host count, with the bit-level breakdown.

IPv6

IPv6 Subnet Calculator

Compress/expand (RFC 5952), prefix maths, /64 counts and scope for IPv6.

IP Address Converter

Dotted ↔ integer ↔ hex ↔ binary, with public/private scope detection.

Reference

Subnet Cheat Sheet

Every CIDR prefix → mask, wildcard, usable hosts and total addresses, in one table.

Email Security Checker

Scan SPF, DMARC, DKIM, MTA-STS, DNSSEC and MX for a domain — one graded report with a prioritised fix list.

DMARC Checker & Generator

Look up and grade any domain’s DMARC policy, or build a correct v=DMARC1 record with the right reporting.

SPF Checker & Generator

Validate SPF, count DNS lookups against the limit of 10, see the include tree and generate a clean record.

DKIM Checker

Verify the DKIM key at a selector, or auto-probe the common Google, Microsoft 365 and Mailchimp selectors.

DNS Propagation Checker

Check whether an A, MX, TXT, CNAME or NS record has propagated across global resolvers.

WHOIS Lookup

A domain’s registrar, registration/expiry dates, nameservers, status and DNSSEC — via RDAP.

SSL Certificate Checker

A site’s live TLS certificate: expiry, trust chain, issuer, key strength and hostname coverage.

Email Blacklist Checker

Check an IP (or a domain’s mail IP) against Spamhaus, Barracuda and other DNSBLs, with delisting links.

Analyzer

Email Header Analyzer

Paste raw email headers to trace the delivery hops, see SPF/DKIM/DMARC results and spot delays.

AI / GPU Calculator

Size any LLM (Llama, Mixtral, Qwen, DeepSeek) to the exact GPUs, VRAM, server & rack build, power, cooling, capex, finance and a cloud-vs-own break-even.

VMware Alternatives Calculator

Leaving Broadcom? Size your estate onto Proxmox, Nutanix, Azure Local or XCP-ng — hosts, hardware BOM, licence saving vs VCF, finance and a 3-year TCO.

TPM Savings Calculator

Cut Dell/HPE/Cisco hardware support 50–70% with third-party maintenance — enter your OEM spend for an indicative saving range and extend support past end-of-life.