All online tools
Every tool opens instantly and works without sign-up. Pick a task below.
Calculators
Internet & networking
- Subnet CalculatorEnter an IP address and a CIDR prefix to get every parameter of the subnet, from the network address to the host count.
- IP CalculatorEnter an IPv4 address and prefix to see the network it belongs to and what kind of address it is.
- CIDR CalculatorDecodes CIDR notation such as 10.0.0.0/8: the range it covers, its mask and how many addresses it contains.
- Subnet Mask CalculatorEnter an IP address and a mask in either form โ 255.255.255.0 or /24. You get every equivalent notation of the mask and the network details.
- IP Range CalculatorShows where an IPv4 block starts and ends, plus the range you can assign to devices.
Developer tools
- JSON FormatterPaste JSON to indent it, squeeze it into one line, or find out exactly where it breaks.
- JSON ValidatorPaste JSON to find out whether it is valid โ and if not, exactly where and why.
- Base64 Encoder / DecoderTurns text into Base64 and back. Accents, non-Latin scripts and emoji are handled correctly.
- URL Encoder / DecoderTurns hello world & more into hello%20world%20%26%20more and back, for query strings, links and APIs.
- UUID GeneratorCreates random version 4 UUIDs, one at a time or as a list of up to 500.
Text
- Character CounterCounts characters with and without spaces, words, lines and paragraphs as you type.
- Word CounterShows the number of words, characters, lines and sentences, plus an estimated reading time.
- Duplicate Line RemoverKeeps only unique lines in a list โ emails, SKUs, keywords, links, anything.
- Case ConverterSwitches text to upper or lower case, or capitalises the first letter of each word or sentence.
- Lorem Ipsum GeneratorCreates placeholder text with an exact number of words and paragraphs for mockups and layouts.
Date & time
- Age CalculatorEnter a date of birth to get the exact age in years, months and days, and the date of the next birthday.
- Date Difference CalculatorWorks out how much time lies between two dates: in days, weeks, months, years, hours and minutes.
- Working Days CalculatorCounts Monday-to-Friday working days between two dates. Add your own holidays as a list.