Developer Tools — Hash, Regex, Color, and IP Lookup in One Tab Set

Four small utilities developers reach for constantly, grouped into one tabbed page so switching between them doesn't mean switching tabs in the browser too: a hash generator, a regex tester, a color converter, and an IP lookup.

Hash Generator

Hash any text string (or upload a file) and get MD5, SHA-1, SHA-256, and SHA-512 digests side by side. Paste a published checksum next to the output to confirm a download hasn't been tampered with, or check what a stored hash should look like for a given input. MD5 and SHA-1 are shown for compatibility and legacy verification only — neither is safe for anything security-sensitive; use SHA-256 or SHA-512 when the hash actually needs to hold up.

Regex Tester

Write a JavaScript regular expression, paste sample text, and see every match highlighted live as you type — far faster than adding a console.log and reloading a page to check whether a pattern actually matches. Global, case-insensitive, multiline, and dotall flags are all supported, plus a replace mode for testing capture-group substitutions before you drop the pattern into real code.

Color Converter

Convert between HEX, RGB, RGBA, HSL, HSLA, and CMYK with a live swatch preview. Handy when a Figma handoff gives you a hex value and your CSS variables are in HSL, or when you're translating a brand color for print and need the CMYK approximation.

IP Lookup

Look up any IP address for its approximate location, ISP, and ASN — or check your own current public IP, detected automatically when the tab loads. Useful for confirming a VPN is actually routing through the country it claims, or figuring out where a suspicious login attempt in your server logs came from.

Common use cases

Validating Indian data formats: Test a PAN card regex (/^[A-Z]{5}[0-9]{4}[A-Z]{1}$/), an Aadhaar-number pattern, or a GST number format against real sample values in the regex tester before it goes into your validation code.

Verifying file integrity: A publisher lists a SHA-256 hash next to a download. Hash your downloaded copy here and compare — a mismatch means the file was altered or corrupted in transit.

Frontend styling work: Pull a hex value from a design file, convert it to HSL for a CSS custom property, and check the swatch matches what the designer intended.

Debugging where a request came from: An access log shows an unfamiliar IP. Paste it into the lookup tab to see the country, ISP, and whether it looks like a legitimate visitor or a bot network.

Tips

Use sample or sanitised data here, not production secrets — never paste a real API key, password, or live customer record into any browser tool, this one included. Everything runs client-side, but the habit matters regardless of where you're testing.

The regex tester runs on JavaScript's regex engine specifically. If the pattern is destined for Python, Java, or Go, dialect differences in lookbehind support and escape sequences mean you should double-check in a language-specific environment before trusting the match behaviour completely.

Limitations

These four are quick-reference utilities, not a replacement for your editor or browser DevTools — there's no code execution and no network request inspection here. For the full write-up on hashing algorithms, encoding formats, or IP geolocation accuracy, the standalone Hash Generator, Color Converter, and IP Lookup pages go into more depth than fits in a shared tab view. Very large inputs (multi-megabyte files, huge blocks of text) may be slow in the browser; for bulk processing, a command-line tool like openssl or jq will be faster.

Frequently Asked Questions

MD5, SHA-1, SHA-256, and SHA-512. All four hashes are generated simultaneously from the same input. For security-sensitive tasks, use SHA-256 or SHA-512 — MD5 and SHA-1 have known vulnerabilities and should only be used for non-security checksums.

g (global — find all matches), i (case-insensitive), m (multiline — ^ and $ match line boundaries), s (dotAll — dot matches newlines), and u (full Unicode support). This uses the JavaScript RegExp engine, which is compatible with most modern languages for common patterns.

HEX, RGB, HSL, HSV, and CMYK — all five major color formats used in web design, UI design, and print publishing. You can enter any format in the text box (e.g. #FF5733, rgb(255,87,51), or hsl(11,100%,60%)) and all other formats update instantly.

The IP Lookup tool uses the public ipapi.co API to retrieve geolocation data. Your IP is sent to ipapi.co to perform the lookup — that is the nature of any IP lookup service. OurTools itself does not log or store your IP address. The geolocation result shows approximate city/region level location, not your exact address.

Hash generation, regex testing, and color conversion all run entirely in your browser — no data leaves your device. The only exception is IP Lookup, which must contact ipapi.co to resolve an IP address. File hashing uses the FileReader API and processes the file locally without uploading it.