CRC-16 Calculator
Compute CRC-16 checksums with multiple variants — CCITT-ZERO, CCITT-FALSE, Modbus, XMODEM.
| Variant | Hex | Decimal | |
|---|---|---|---|
| CRC-16/CCITT-ZERO | 0x992A | 39210 | |
| CRC-16/CCITT-FALSE | 0x4D25 | 19749 | |
| CRC-16/MODBUS | 0xDAED | 56045 | |
| CRC-16/XMODEM | 0x992A | 39210 |
CRC-16 variants compared
CRC-16 (Cyclic Redundancy Check) produces a 16-bit checksum used to detect accidental data corruption. Different protocols use different polynomial, initial value, reflection, and XOR-out settings. The most common are Modbus (industrial automation), XMODEM (file transfer), and various CCITT variants (Bluetooth, SD cards, serial protocols). All variants are computed purely in JavaScript — no server round-trip.
Private & free — this tool runs entirely in your browser.
Recommended: IndieKit — Ship your Next.js startup in days.affiliate
Related Developer Utilities tools
RegExp Tester
Test regular expressions and inspect matches locally.
Regex Visualizer
Visual regex pattern diagram with live match highlighting and capture group annotations.
Subnet Calculator
Compute CIDR subnets, usable hosts, and network ranges.
Cron Parser
Translate cron syntax into plain English.
URL Parser
Break a URL into protocol, host, path, and query parts.
HTML Previewer
Paste HTML and see it rendered live in a safe, sandboxed preview.
HTTP Status Code Reference
Search and look up every HTTP status code and its meaning.
MIME Type Lookup
Find the MIME type for a file extension, or the extensions for a MIME type.