CIDR Calculator is a free, browser-based web development and coding tool. Calculate network address, broadcast, first/last host, and number of IPs from CIDR notation.
Web developers, software engineers, and DevOps professionals use CIDR Calculator every day to save time and skip the overhead of desktop software or paid services. No installation, no account, and no technical knowledge required — just enter your values into CIDR Calculator and get results in seconds. Your files never leave your browser — full privacy by design.
Advertisement
How to use CIDR Calculator
1
Enter CIDR
Enter an IP in CIDR notation (e.g. 192.168.1.0/24).
2
Calculate
View network range details.
Use Cases
- Debugging and validating data formats during API development
- Preparing test fixtures and sample payloads
- Encoding and decoding data for integrations and authentication flows
- Formatting and linting configuration files before deployment
Key Benefits
- 100% free with no usage limits, watermarks, or hidden fees
- No account or sign-up required — use it instantly
- Works in all modern browsers on desktop, tablet, and mobile
- Privacy-first: all processing runs locally, files never leave your device
- Instant real-time results — updates as you type
- Based on standard industry-accepted formulas
- Results displayed clearly with full breakdown