DevOps tools
Cron expressions, Docker Compose, file permissions, subnets, and server configs.
Convert Unix file permissions between octal (755), symbolic (rwxr-xr-x), and checkboxes.
Expand a CIDR block into its address range and host counts, or turn a first and last IP into the minimal set of CIDR blocks.
Build a cron expression from dropdowns for each field, with a plain-English description and the next run times as you go.
Paste a cron expression and get a plain-English explanation plus the next run times.
Assemble a Content-Security-Policy from common directives and source lists, with a strict starter preset and both header and meta output.
Convert docker run commands into docker-compose services.
Generate commented nginx config for single-path, domain, HTTP-to-HTTPS, www, trailing-slash, and bulk redirects.
Enter an IPv4 address and mask to get the network and broadcast addresses, usable host range, host count, and wildcard mask.
About DevOps tools
These tools cover the small, error-prone artifacts of running infrastructure: cron expressions, file permission bits, subnet masks, Content-Security-Policy headers, and nginx redirect rules. The cron parser translates an expression into plain English and lists its next run times, and the generator works the other way — build the schedule from dropdowns and copy the result. The chmod calculator converts freely between octal, symbolic notation, and checkboxes, including the setuid, setgid, and sticky bits.
The networking calculators expand an IPv4 address and mask into network and broadcast addresses, usable host ranges, and wildcard masks, or turn an IP range into the minimal set of CIDR blocks — useful for firewall rules, VPC planning, and allowlists. The Docker converter rewrites a long docker run command as a docker-compose service, and the CSP and nginx generators produce commented, copy-ready config instead of leaving you to remember directive syntax.
Like everything on this site, these run locally in your browser, so pasting an internal subnet, a production crontab, or a docker run command with environment variables in it doesn't send that information anywhere.