Free tools
Everyday tools forIT & network engineers.
The calculators and checks the Cloudku engineering team uses every day. Free, no sign-up, and they run right in your browser.
Subnet Calculator
Work out network, broadcast, host range, and subnet splits for IPv4 and IPv6.
Open toolWhat Is My IP
See your public IP address, ASN, ISP, and connection location.
Open toolBandwidth Calculator
Convert Mbps to monthly TB of transfer, and estimate file transfer time.
Open toolRack Power Calculator
Estimate power (watts, amps, kVA), heat, and rack space for colocation.
Open toolDNS Lookup
Look up A, AAAA, MX, NS, TXT, CNAME, and more, compared across three public resolvers.
Open toolSPF, DKIM & DMARC Checker
Check your domain’s email security and generate correct SPF and DMARC records.
Open toolUptime & SLA Calculator
Turn an SLA percentage into allowed downtime per day, month, and year.
Open toolRAID Calculator
Compare usable capacity and fault tolerance for RAID 0, 1, 5, 6, and 10.
Open tool