Timestamps, number bases, colours, cron lines, encodings and curl commands, read both ways
Everything here runs in your browser. Files are never uploaded.A great deal of a working day goes on turning one representation of the same thing into another: an epoch number into a date you can reason about, a hex value into a colour you can see, a cron line into a sentence, an encoded parameter into the text somebody actually typed. These do that in both directions, instantly and in the browser, so the value you are decoding stays where it is.
Unix Timestamp Converter goes from epoch to a date and back in any time zone, and it is the place to settle whether a field is in seconds or milliseconds: a ten-digit number is seconds, a thirteen-digit one is milliseconds, and treating one as the other lands you in 1970 or in the year 54,000.
Cron Expression Builder assembles a schedule from menus, reads it back in plain English and lists the next few runs. The next-run list is the part that catches mistakes, because a job that should run nightly and is about to run every minute is obvious in a list and invisible in five asterisks.
Number Base Converter handles binary, octal, decimal, hex and any base up to 36, exactly at any size, with two's complement for negatives. Color Converter moves between HEX, RGB, HSL, HWB, OKLCH and CMYK and checks the contrast of a pair, which is the number an accessibility audit will ask for.
URL Encoder / Decoder percent-encodes and decodes, and breaks a link into its parts. Base64 encodes and decodes text and files, including data URIs for images. Base64 is an encoding and not encryption: anything encoded with it is readable by anybody, and it exists to move bytes through channels that expect text.
Data Converter moves between JSON, YAML, XML, CSV, TSV, TOML and INI, which is what a config file becomes when the tool that reads it changes.
curl Converter turns a curl command, of the kind your browser's network tab copies, into fetch, Node, Python, PowerShell or HTTPie. That copied command carries live cookies and authorisation headers, which is precisely why this conversion should not happen on somebody else's server.
No. Every conversion here runs in the browser, which matters most for the curl converter, because a command copied from a network tab usually contains live cookies and an authorisation header.
Count the digits. Ten digits is seconds and thirteen is milliseconds for any date near today. Unix time counts seconds since 1 January 1970 UTC, and Java, JavaScript and many APIs use milliseconds instead.
No. It is a way of writing binary data as text so it can pass through channels that expect text. Anyone can decode it instantly, so it protects nothing and adds about a third to the size.
Minute 0, hour 2, any day of the month, any month, day of week 1: two in the morning every Monday. The builder writes the sentence and lists the next few run times so you can check before deploying it.
HEX or RGB for anything on a screen, HSL when you want to adjust lightness by hand, OKLCH when you want two colours to look equally bright, and CMYK only when a printer has asked for it.
Usually a parameter that was encoded twice, so a percent sign became %25. Decode once and look: if you see %2520 you have found it.