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+[[query-dsl-fuzzy-query]]
+=== Fuzzy Query
+
+The fuzzy query uses similarity based on Levenshtein edit distance for
+`string` fields, and a `+/-` margin on numeric and date fields.
+
+==== String fields
+
+The `fuzzy` query generates all possible matching terms that are within  the
+maximum edit distance specified in `fuzziness` and then checks the term
+dictionary to find out which of those generated terms actually exist in the
+index.
+
+Here is a simple example:
+
+[source,js]
+--------------------------------------------------
+{
+    "fuzzy" : { "user" : "ki" }
+}
+--------------------------------------------------
+
+Or with more advanced settings:
+
+[source,js]
+--------------------------------------------------
+{
+    "fuzzy" : {
+        "user" : {
+            "value" :         "ki",
+            "boost" :         1.0,
+            "fuzziness" :     2,
+            "prefix_length" : 0,
+            "max_expansions": 100
+        }
+    }
+}
+--------------------------------------------------
+
+[float]
+===== Parameters
+
+[horizontal]
+`fuzziness`::
+
+    The maximum edit distance. Defaults to `AUTO`. See <<fuzziness>>.
+
+`prefix_length`::
+
+    The number of initial characters which will not be ``fuzzified''. This
+    helps to reduce the number of terms which must be examined. Defaults
+    to `0`.
+
+`max_expansions`::
+
+    The maximum number of terms that the `fuzzy` query will expand to.
+    Defaults to `0`.
+
+
+WARNING: this query can be very heavy if `prefix_length` and `max_expansions`
+are both set to their defaults of `0`. This could cause every term in the
+index to be examined!
+
+
+[float]
+==== Numeric and date fields
+
+Performs a <<query-dsl-range-query>> ``around'' the value using the
+`fuzziness` value as a `+/-` range, where:
+
+    -fuzziness <= field value <= +fuzziness
+
+For example:
+
+[source,js]
+--------------------------------------------------
+{
+    "fuzzy" : {
+        "price" : {
+            "value" : 12,
+            "fuzziness" : 2
+        }
+    }
+}
+--------------------------------------------------
+
+Will result in a range query between 10 and 14. Date fields support
+<<time-units,time values>>, eg:
+
+[source,js]
+--------------------------------------------------
+{
+    "fuzzy" : {
+        "created" : {
+            "value" : "2010-02-05T12:05:07",
+            "fuzziness" : "1d"
+        }
+    }
+}
+--------------------------------------------------
+
+See <<fuzziness>> for more details about accepted values.