DevOps & Network
Cron expression builder, chmod calculator and hex/IP converter
All 3 DevOps and network tools run entirely in your browser. Build cron expressions with a visual scheduler, compute chmod permissions and convert hex to IPv4 addresses — no install, no server, no account.
3 tools
Cron Expression Builder
Build and explain cron expressions visually
Chmod Calculator
Calculate Unix file permission codes with a visual checkbox grid
IP / Hex / Decimal Converter
Convert IPv4 addresses between dotted-decimal, hexadecimal and 32-bit integer representations
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About DevOps & Network
DevOps, infrastructure and network utilities for engineers and sysadmins. All 3 tools run 100% client-side with instant output — from scheduler configuration and permission management to network address arithmetic.
Features
- ✓Cron expression builder — visual editor with natural-language schedule description and next 5 run times preview
- ✓Chmod calculator — compute octal and symbolic permission strings visually, with per-user breakdown (owner, group, others)
- ✓Hex/IP converter — convert between hexadecimal and dotted-decimal IPv4 address notation in both directions
Common Use Cases
- Build a cron expression for a scheduled job and verify the next 5 run times before deploying
- Calculate the correct chmod octal value before running chmod on a production server
- Convert a hex-encoded IP address from a packet capture or syslog to dotted-decimal notation
Frequently Asked Questions
QIs my data sent to a server?
No. All generation and calculation runs entirely in your browser. Nothing you enter is transmitted.
QDoes the cron builder support all cron dialects?
Yes. It supports standard 5-field POSIX cron (minute hour dom month dow) as well as the 6-field extended syntax used by Quartz, AWS EventBridge and other schedulers with a seconds field.
See Also
- Cron BuilderBuild and validate cron expressions visually
- Hex/IP ConverterConvert between hex and dotted-decimal IPv4 addresses
- Chmod CalculatorCompute chmod permissions visually with octal output
- Security ToolsPassword generator, JWT decoder, RSA/SSH key gen and more
- Developer ToolsRegex tester, diff, JSONPath