Developer & text tools
Small utilities for the things developers and writers look up every day: IDs, timestamps, cron schedules, checksums, regular expressions and colors. They run entirely in the page, so it's safe to paste logs, config or payloads that you'd never want to send to a stranger's server.
All developer and text tools
Unix Timestamp Converter
Epoch to a human date and back.
UUID Generator
Random v4 or time-ordered v7 UUIDs.
Color Converter
Convert HEX, RGB, HSL & extract palettes.
Hash & Checksum
MD5 / SHA of text or a file, and verify.
Cron Expression Explainer
Read a crontab schedule in plain English.
Find & Replace
Search & replace text, with regex.
Which tool do I need?
- Unique IDs for database rows or test data UUID Generator →
- An epoch number in a log, or a date to convert to one Unix Timestamp Converter →
- A crontab line you need to read or check Cron Expression Explainer →
- Checking a download against its published SHA-256 Hash & Checksum →
- Bulk-editing text, with or without regex Find & Replace →
- Converting HEX, RGB and HSL, or pulling a palette from an image Color Converter →
Safe to paste into
Logs, API responses and config files often contain tokens, internal hostnames and customer data. These tools make no network requests with what you paste: hashing uses the browser's Web Crypto API, UUIDs come from its secure random generator, and the cron and regex parsing happen in plain JavaScript on the page. You can check this yourself by opening your browser's developer tools and watching the Network tab while you use them.
Good to know
Unix timestamps are always UTC; the converter shows them in your local time zone as well. The regex tool uses JavaScript's regular-expression flavor, including lookbehind and named groups. For checking a download, prefer SHA-256: MD5 still catches accidental corruption, but it's no longer safe against deliberate tampering (see how to verify a file checksum).
Related guides
Frequently asked questions
Is anything I paste sent to a server?
No. All processing happens in JavaScript inside the page, and the tools make no network requests with your input. You can confirm it in your browser's network inspector.
Is MD5 still safe to use?
For spotting accidental corruption in a download, yes. For security — proving a file wasn't deliberately altered — no: practical MD5 and SHA-1 collisions exist. Use SHA-256 when the publisher provides it.
Which time zone does the timestamp converter use?
A Unix timestamp counts seconds since 1 January 1970 in UTC, so it has no time zone of its own. The converter shows the result in UTC, ISO 8601 and your browser's local time.
Should I use UUID v4 or v7?
Use v7 for database primary keys: it's time-ordered, so new rows are inserted in index order. Use v4 when an ID must not reveal when it was created.