Dev Utilities Pro · Bedrocka Tools
Developer utilities without the SaaS paywall.
Cron expressions, Unix timestamps, number base conversion — the tools every developer reaches for multiple times a week. Most online versions are thin wrappers with no spec citations, no algorithm transparency, and no human accountability. This site is the opposite: every formula cites the primary standard, every calculator is reviewed quarterly by a named engineer.
Calculators
Pick the tool you actually need.
Learn
Concepts behind the utilities.
Scheduling
Cron Expression Syntax — A Developer's Field Guide
POSIX cron is five fields. Quartz adds a sixth. AWS EventBridge requires ? in one of dom or dow. GitHub Actions runs UTC only. Here is the complete field-level reference with the dialect traps that actually bite you in production.
Time & Date
Unix Timestamps Explained — Epoch, Y2K38, and ISO 8601 vs RFC 3339
A Unix timestamp is the number of non-leap seconds since 1970-01-01T00:00:00Z per POSIX.1-2017 §4.16. Values above 10¹² are milliseconds. The 32-bit signed maximum hits 2038-01-19T03:14:07Z. Here is everything you need to handle them correctly.
What makes this different
Three things every Bedrocka Tools site does that the incumbents don't.
Open-source math
Every calculator's formula is published as TypeScript with Vitest tests in a public repo. Click "View source" in any math accordion to see the actual implementation. Crontab.guru and EpochConverter hide their logic. We publish it.
Browse the math →Primary-source citations only
Every field range, epoch definition, and encoding rule links to the original document — IEEE Std 1003.1, RFC 3339, RFC 4648, IANA timezone database, Knuth TAOCP, Intel SDM. No "according to industry sources" hedging. The citation is the proof.
Read the methodology →Named engineer, real bio
Reviewed and signed by Byron Malone— a decade of working at the intersection of software systems and operational reality. Not a content mill.
Read Byron's bio →Part of Bedrocka Tools
Dev Utilities Pro is Site #15 in the Bedrocka Tools portfolio — a family of source-cited calculator sites built on the same open-source formula library. Every site shares the same methodology, the same primary-source discipline, and the same named reviewer.
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