diff --git a/encodings/ascii-compat-generated.js b/encodings/ascii-compat-generated.js
new file mode 100644
index 0000000..25580ac
--- /dev/null
+++ b/encodings/ascii-compat-generated.js
@@ -0,0 +1,381 @@
+
+// Generated data for ASCII-compatible codecs. Don't edit manually. Regenerate using generation/gen-ascii-compat.js script.
+module.exports = {
+  "437": true,
+  "737": true,
+  "775": true,
+  "808": true,
+  "850": true,
+  "852": true,
+  "855": true,
+  "856": true,
+  "857": true,
+  "858": true,
+  "860": true,
+  "861": true,
+  "862": true,
+  "863": true,
+  "865": true,
+  "866": true,
+  "869": true,
+  "874": true,
+  "922": true,
+  "932": true,
+  "936": true,
+  "949": true,
+  "950": true,
+  "1046": true,
+  "1124": true,
+  "1125": true,
+  "1129": true,
+  "1133": true,
+  "1161": true,
+  "1162": true,
+  "1163": true,
+  "1250": true,
+  "1251": true,
+  "1252": true,
+  "1253": true,
+  "1254": true,
+  "1255": true,
+  "1256": true,
+  "1257": true,
+  "1258": true,
+  "10000": true,
+  "10006": true,
+  "10007": true,
+  "10029": true,
+  "10079": true,
+  "10081": true,
+  "20866": true,
+  "21866": true,
+  "28591": true,
+  "28592": true,
+  "28593": true,
+  "28594": true,
+  "28595": true,
+  "28596": true,
+  "28597": true,
+  "28598": true,
+  "28599": true,
+  "28600": true,
+  "28601": true,
+  "28603": true,
+  "28604": true,
+  "28605": true,
+  "28606": true,
+  "ansix3.4": true,
+  "ansix3.41968": true,
+  "ansix3.41986": true,
+  "arabic": true,
+  "arabic8": true,
+  "armscii8": true,
+  "ascii": true,
+  "ascii8bit": true,
+  "asmo708": true,
+  "base64": true,
+  "big5": true,
+  "big5hkscs": true,
+  "binary": true,
+  "celtic": true,
+  "celtic8": true,
+  "cesu8": true,
+  "chinese": true,
+  "cnbig5": true,
+  "cp1046": true,
+  "cp1124": true,
+  "cp1125": true,
+  "cp1129": true,
+  "cp1133": true,
+  "cp1161": true,
+  "cp1162": true,
+  "cp1163": true,
+  "cp1250": true,
+  "cp1251": true,
+  "cp1252": true,
+  "cp1253": true,
+  "cp1254": true,
+  "cp1255": true,
+  "cp1256": true,
+  "cp1257": true,
+  "cp1258": true,
+  "cp20866": true,
+  "cp21866": true,
+  "cp28591": true,
+  "cp28592": true,
+  "cp28593": true,
+  "cp28594": true,
+  "cp28595": true,
+  "cp28596": true,
+  "cp28597": true,
+  "cp28598": true,
+  "cp28599": true,
+  "cp28600": true,
+  "cp28601": true,
+  "cp28603": true,
+  "cp28604": true,
+  "cp28605": true,
+  "cp28606": true,
+  "cp367": true,
+  "cp437": true,
+  "cp737": true,
+  "cp775": true,
+  "cp808": true,
+  "cp819": true,
+  "cp850": true,
+  "cp852": true,
+  "cp855": true,
+  "cp856": true,
+  "cp857": true,
+  "cp858": true,
+  "cp860": true,
+  "cp861": true,
+  "cp862": true,
+  "cp863": true,
+  "cp865": true,
+  "cp866": true,
+  "cp869": true,
+  "cp874": true,
+  "cp922": true,
+  "cp932": true,
+  "cp936": true,
+  "cp949": true,
+  "cp950": true,
+  "cpgr": true,
+  "csascii": true,
+  "csbig5": true,
+  "cseuckr": true,
+  "csgb2312": true,
+  "cshproman8": true,
+  "csibm1046": true,
+  "csibm1124": true,
+  "csibm1125": true,
+  "csibm1129": true,
+  "csibm1133": true,
+  "csibm1161": true,
+  "csibm1162": true,
+  "csibm1163": true,
+  "csibm437": true,
+  "csibm737": true,
+  "csibm775": true,
+  "csibm850": true,
+  "csibm852": true,
+  "csibm855": true,
+  "csibm856": true,
+  "csibm857": true,
+  "csibm858": true,
+  "csibm860": true,
+  "csibm861": true,
+  "csibm862": true,
+  "csibm863": true,
+  "csibm865": true,
+  "csibm866": true,
+  "csibm869": true,
+  "csibm922": true,
+  "csiso58gb231280": true,
+  "csisolatin1": true,
+  "csisolatin2": true,
+  "csisolatin3": true,
+  "csisolatin4": true,
+  "csisolatin5": true,
+  "csisolatin6": true,
+  "csisolatinarabic": true,
+  "csisolatincyrillic": true,
+  "csisolatingreek": true,
+  "csisolatinhebrew": true,
+  "cskoi8r": true,
+  "csksc56011987": true,
+  "csmacintosh": true,
+  "cspc775baltic": true,
+  "cspc850multilingual": true,
+  "cspc862latinhebrew": true,
+  "cspc8codepage437": true,
+  "cspcp852": true,
+  "csshiftjis": true,
+  "cyrillic": true,
+  "ecma114": true,
+  "ecma118": true,
+  "elot928": true,
+  "euccn": true,
+  "eucjp": true,
+  "euckr": true,
+  "gb18030": true,
+  "gb2312": true,
+  "gb23121980": true,
+  "gb231280": true,
+  "gbk": true,
+  "georgianacademy": true,
+  "georgianps": true,
+  "greek": true,
+  "greek8": true,
+  "hebrew": true,
+  "hebrew8": true,
+  "hex": true,
+  "hproman8": true,
+  "ibm1046": true,
+  "ibm1051": true,
+  "ibm1124": true,
+  "ibm1125": true,
+  "ibm1129": true,
+  "ibm1133": true,
+  "ibm1161": true,
+  "ibm1162": true,
+  "ibm1163": true,
+  "ibm1168": true,
+  "ibm367": true,
+  "ibm437": true,
+  "ibm737": true,
+  "ibm775": true,
+  "ibm808": true,
+  "ibm819": true,
+  "ibm850": true,
+  "ibm852": true,
+  "ibm855": true,
+  "ibm856": true,
+  "ibm857": true,
+  "ibm858": true,
+  "ibm860": true,
+  "ibm861": true,
+  "ibm862": true,
+  "ibm863": true,
+  "ibm865": true,
+  "ibm866": true,
+  "ibm869": true,
+  "ibm878": true,
+  "ibm922": true,
+  "iso646.irv": true,
+  "iso646us": true,
+  "iso88591": true,
+  "iso885910": true,
+  "iso885911": true,
+  "iso885913": true,
+  "iso885914": true,
+  "iso885915": true,
+  "iso885916": true,
+  "iso88592": true,
+  "iso88593": true,
+  "iso88594": true,
+  "iso88595": true,
+  "iso88596": true,
+  "iso88597": true,
+  "iso88598": true,
+  "iso88599": true,
+  "isoceltic": true,
+  "isoir100": true,
+  "isoir101": true,
+  "isoir109": true,
+  "isoir110": true,
+  "isoir126": true,
+  "isoir127": true,
+  "isoir138": true,
+  "isoir144": true,
+  "isoir148": true,
+  "isoir149": true,
+  "isoir157": true,
+  "isoir166": true,
+  "isoir179": true,
+  "isoir199": true,
+  "isoir203": true,
+  "isoir226": true,
+  "isoir58": true,
+  "isoir6": true,
+  "koi8r": true,
+  "koi8ru": true,
+  "koi8t": true,
+  "koi8u": true,
+  "korean": true,
+  "ksc5601": true,
+  "ksc56011987": true,
+  "ksc56011989": true,
+  "l1": true,
+  "l10": true,
+  "l2": true,
+  "l3": true,
+  "l4": true,
+  "l5": true,
+  "l6": true,
+  "l7": true,
+  "l8": true,
+  "l9": true,
+  "latin1": true,
+  "latin10": true,
+  "latin2": true,
+  "latin3": true,
+  "latin4": true,
+  "latin5": true,
+  "latin6": true,
+  "latin7": true,
+  "latin8": true,
+  "latin9": true,
+  "mac": true,
+  "maccenteuro": true,
+  "maccroatian": true,
+  "maccyrillic": true,
+  "macgreek": true,
+  "maciceland": true,
+  "macintosh": true,
+  "macroman": true,
+  "macromania": true,
+  "macthai": true,
+  "macturkish": true,
+  "macukraine": true,
+  "msansi": true,
+  "msarab": true,
+  "mscyrl": true,
+  "msee": true,
+  "msgreek": true,
+  "mshebr": true,
+  "mskanji": true,
+  "msturk": true,
+  "pt154": true,
+  "r8": true,
+  "rk1048": true,
+  "roman8": true,
+  "shiftjis": true,
+  "sjis": true,
+  "strk10482002": true,
+  "thai": true,
+  "thai8": true,
+  "tis620": true,
+  "tis620.25291": true,
+  "tis620.25330": true,
+  "tis6200": true,
+  "turkish": true,
+  "turkish8": true,
+  "ucs2": true,
+  "unicode11utf8": true,
+  "us": true,
+  "usascii": true,
+  "utf16le": true,
+  "utf8": true,
+  "win1250": true,
+  "win1251": true,
+  "win1252": true,
+  "win1253": true,
+  "win1254": true,
+  "win1255": true,
+  "win1256": true,
+  "win1257": true,
+  "win1258": true,
+  "win874": true,
+  "winbaltrim": true,
+  "windows1250": true,
+  "windows1251": true,
+  "windows1252": true,
+  "windows1253": true,
+  "windows1254": true,
+  "windows1255": true,
+  "windows1256": true,
+  "windows1257": true,
+  "windows1258": true,
+  "windows31j": true,
+  "windows874": true,
+  "windows932": true,
+  "windows936": true,
+  "windows949": true,
+  "windows950": true,
+  "xgbk": true,
+  "xroman8": true,
+  "xsjis": true,
+  "xxbig5": true
+}
\ No newline at end of file
diff --git a/generation/gen-ascii-compat.js b/generation/gen-ascii-compat.js
new file mode 100644
index 0000000..c042857
--- /dev/null
+++ b/generation/gen-ascii-compat.js
@@ -0,0 +1,58 @@
+var fs = require("fs"),
+    path = require("path");
+
+var destFileName = "encodings/ascii-compat-generated.js";
+
+var encodings = require(path.join(__dirname, "..", "encodings")),
+    names = Object.keys(encodings),
+    // start off with some known ASCII-compatible charsets that are supported
+    // internally
+    compat = [ "utf8", "unicode11utf8", "ascii" ];
+
+for (var i = 0, len = names.length, enc; i < len; ++i) {
+  enc = names[i];
+  if (~compat.indexOf(enc) || typeof encodings[enc] === "function")
+    continue;
+
+  var done = false,
+      nextenc = enc,
+      opts;
+  while (!done) {
+    var codec = encodings[nextenc];
+
+    switch (typeof codec) {
+      case "string": // Direct alias to other encoding.
+        nextenc = codec;
+        break;
+
+      case "object": // Alias with options. Can be layered.
+        if (!opts) {
+          opts = codec;
+          opts.encodingName = nextenc;
+        } else {
+          for (var key in codec)
+            opts[key] = codec[key];
+        }
+
+        nextenc = codec.type;
+        break;
+
+      default:
+        done = true;
+    }
+  }
+
+  if (opts && opts.chars && opts.chars.length === 128)
+    compat.push(enc);
+}
+
+compat.sort();
+
+encodings = {};
+for (var i = 0, len = compat.length; i < len; ++i)
+  encodings[compat[i]] = true;
+
+// Write encodings.
+fs.writeFileSync(path.join(__dirname, "..", destFileName),
+    "\n// Generated data for ASCII-compatible codecs. Don't edit manually. Regenerate using generation/gen-ascii-compat.js script.\n"+
+    "module.exports = "+JSON.stringify(encodings, undefined, "  "));
diff --git a/lib/index.js b/lib/index.js
index 0775589..6319c80 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -9,6 +9,8 @@ iconv.encodings = null;
 iconv.defaultCharUnicode = '�';
 iconv.defaultCharSingleByte = '?';
 
+var RE_STRIP_CHARS = /[^0-9a-z]|:\d{4}$/g;
+
 // Public API.
 iconv.encode = function encode(str, encoding, options) {
     str = "" + (str || ""); // Ensure string.
@@ -59,7 +61,7 @@ iconv.getCodec = function getCodec(encoding) {
         iconv.encodings = require("../encodings"); // Lazy load all encoding definitions.
     
     // Canonicalize encoding name: strip all non-alphanumeric chars and appended year.
-    var enc = (''+encoding).toLowerCase().replace(/[^0-9a-z]|:\d{4}$/g, "");
+    var enc = (''+encoding).toLowerCase().replace(RE_STRIP_CHARS, "");
 
     // Traverse iconv.encodings to find actual codec.
     var codecData, codecOptions;
@@ -106,6 +108,14 @@ iconv.getCodec = function getCodec(encoding) {
     }
 }
 
+var ASCII_COMPAT_MAP;
+iconv.asciiCompatible = function asciiCompatible(enc) {
+  if (!ASCII_COMPAT_MAP)
+    ASCII_COMPAT_MAP = require('../encodings/ascii-compat-generated');
+  enc = enc.toLowerCase().replace(RE_STRIP_CHARS, '');
+  return (ASCII_COMPAT_MAP[enc] || false);
+};
+
 // Load extensions in Node. All of them are omitted in Browserify build via 'browser' field in package.json.
 var nodeVer = typeof process !== 'undefined' && process.versions && process.versions.node;
 if (nodeVer) {