diff --git a/packages/crc32-cli/bin/crc32.njs b/packages/crc32-cli/bin/crc32.njs
new file mode 100755
index 0000000..80c98b9
--- /dev/null
+++ b/packages/crc32-cli/bin/crc32.njs
@@ -0,0 +1,9 @@
+#!/usr/bin/env node
+/* crc32.js (C) 2014-present SheetJS -- http://sheetjs.com */
+/* eslint-env node */
+/* vim: set ts=2 ft=javascript: */
+/*jshint node:true */
+
+var cli = require('../');
+
+cli();
diff --git a/packages/crc32-cli/index.js b/packages/crc32-cli/index.js
new file mode 100644
index 0000000..949b36f
--- /dev/null
+++ b/packages/crc32-cli/index.js
@@ -0,0 +1,94 @@
+/* index.js (C) 2020-present SheetJS -- http://sheetjs.com */
+/* eslint-env node */
+/* vim: set ts=2 ft=javascript: */
+/*jshint node:true */
+
+/*:CRC32Module*/
+var X = require('crc-32');
+
+function help()/*:number*/ {
+	[
+		"usage: crc32 [options] [filename]",
+		"",
+		"Options:",
+		"    -h, --help           output usage information",
+		"    -V, --version        output the version number",
+		"    -S, --seed=<n>       use integer seed as starting value (rolling CRC)",
+		"    -H, --hex-seed=<h>   use hex seed as starting value (rolling CRC)",
+		"    -d, --signed         print result with format `%d` (default)",
+		"    -u, --unsigned       print result with format `%u`",
+		"    -x, --hex            print result with format `%0.8x`",
+		"    -X, --HEX            print result with format `%0.8X`",
+		"    -c, --crc32c         use CRC32C (Castagnoli)",
+		"    -F, --format=<s>     use specified printf format",
+		"",
+		"Set filename = '-' or pipe data into crc32 to read from stdin",
+		"Default output mode is signed (-d)",
+		""
+	].forEach(function (l) { console.log(l); });
+	return 0;
+}
+
+function version()/*:number*/ { console.log(X.version); return 0; }
+
+var fs = require('fs');
+require('exit-on-epipe');
+
+function die(msg/*:string*/, ec/*:?number*/)/*:void*/ { console.error(msg); process.exit(ec || 0); }
+
+function run() {
+	var args/*:Array<string>*/ = process.argv.slice(2);
+	var filename/*:string*/ = "";
+	var fmt/*:string*/ = "";
+	var seed = 0, r = 10;
+
+	for(var i = 0; i < args.length; ++i) {
+		var arg = args[i];
+		if(arg.charCodeAt(0) != 45) { if(filename === "") filename = arg; continue; }
+		var m = arg.indexOf("=") == -1 ? arg : arg.substr(0, arg.indexOf("="));
+		switch(m) {
+			case "-": filename = "-"; break;
+
+			case "--help": case "-h": process.exit(help()); break;
+			case "--version": case "-V": process.exit(version()); break;
+
+			case "--crc32c": case "-c": try { X = require('../crc32c'); } catch(e) { X = require('crc-32/crc32c'); } break;
+
+			case "--signed": case "-d": fmt = "%d"; break;
+			case "--unsigned": case "-u": fmt = "%u"; break;
+			case "--hex": case "-x": fmt = "%0.8x"; break;
+			case "--HEX": case "-X": fmt = "%0.8X"; break;
+			case "--format": case "-F":
+				fmt = ((m!=arg) ? arg.substr(m.length+1) : args[++i])||""; break;
+
+			case "--hex-seed": case "-H": r = 16;
+			/* falls through */
+			case "--seed": case "-S":
+				seed=parseInt((m!=arg) ? arg.substr(m.length+1) : args[++i], r)||0; break;
+
+			default: die("crc32: unrecognized option `" + arg + "'", 22);
+		}
+	}
+
+	if(!process.stdin.isTTY) filename = filename || "-";
+	if(filename.length===0) die("crc32: must specify a filename ('-' for stdin)",1);
+
+	var crc32 = seed;
+	// $FlowIgnore -- Writable is callable but type sig disagrees
+	var writable = require('stream').Writable();
+	writable._write = function(chunk, e, cb) { crc32 = X.buf(chunk, crc32); cb(); };
+	writable._writev = function(chunks, cb) {
+		chunks.forEach(function(c) { crc32 = X.buf(c.chunk, crc32);});
+		cb();
+	};
+	writable.on('finish', function() {
+		console.log(fmt === "" ? crc32 : require("printj").sprintf(fmt, crc32));
+	});
+
+	if(filename === "-") process.stdin.pipe(writable);
+	else if(fs.existsSync(filename)) fs.createReadStream(filename).pipe(writable);
+	else die("crc32: " + filename + ": No such file or directory", 2);
+} 
+
+module.exports = run;
+
diff --git a/packages/crc32-cli/package.json b/packages/crc32-cli/package.json
new file mode 100644
index 0000000..33161c4
--- /dev/null
+++ b/packages/crc32-cli/package.json
@@ -0,0 +1,16 @@
+{
+	"name": "crc32-cli",
+	"version": "1.0.1",
+	"author": "sheetjs",
+	"description": "Command-line interface for crc32",
+	"bin": {
+		"crc32-cli": "bin/crc32.njs"
+	},
+	"main": "index.js",
+	"dependencies": {
+		"crc-32": "^1.2.1",
+		"exit-on-epipe": "~1.0.1"
+	},
+	"license": "Apache-2.0"
+}
+