diff --git a/CONTRIBUTORS.markdown b/CONTRIBUTORS.markdown
index 8466a7fff..e5e77f69f 100644
--- a/CONTRIBUTORS.markdown
+++ b/CONTRIBUTORS.markdown
@@ -19,3 +19,4 @@ The format for this list: name, GitHub handle, and then optional blurb about wha
 * Billy Kaplan (@billy1kaplan)
 * Tomas Mikula (@TomasMikula)
 * William Carroll (@wpcarro)
+* Scott Christopher (@scott-christopher)
diff --git a/parser-typechecker/src/Unison/Lexer.hs b/parser-typechecker/src/Unison/Lexer.hs
index b159e7c89..ab9e86101 100644
--- a/parser-typechecker/src/Unison/Lexer.hs
+++ b/parser-typechecker/src/Unison/Lexer.hs
@@ -30,6 +30,7 @@ data Err
   | InvalidShortHash String
   | Both Err Err
   | MissingFractional String -- ex `1.` rather than `1.04`
+  | MissingExponent String -- ex `1e` rather than `1e3`
   | UnknownLexeme
   | TextLiteralMissingClosingQuote String
   | InvalidEscapeCharacter Char
@@ -507,11 +508,24 @@ numericLit = go
       (fractional@(_:_), []) ->
         pure $ pure (sign ++ num ++ "." ++ fractional, [])
       (fractional@(_:_), c:rem)
+        | c `elem` "eE" -> goExp (sign ++ num ++ "." ++ fractional) rem
         | isSep c -> pure $ pure (sign ++ num ++ "." ++ fractional, c:rem)
         | otherwise -> pure Nothing
       ([], _) -> Left (MissingFractional (sign ++ num ++ "."))
+    (num@(_:_), c:rem) | c `elem` "eE" -> goExp (sign ++ num) rem
     (num@(_:_), c:rem) -> pure $ pure (sign ++ num, c:rem)
     ([], _) -> pure Nothing
+  goExp signNum rem = case rem of
+    ('+':s) -> goExp' signNum "+" s
+    ('-':s) -> goExp' signNum "-" s
+    s       -> goExp' signNum ""  s 
+  goExp' signNum expSign exp = case span isDigit exp of
+    ((_:_), []) ->
+      pure $ pure (signNum ++ "e" ++ expSign ++ exp, [])
+    (exp'@(_:_), c:rem)
+      | isSep c -> pure $ pure (signNum ++ "e" ++ expSign ++ exp', c:rem)
+      | otherwise -> pure Nothing
+    ([], _) -> Left (MissingExponent (signNum ++ "e" ++ expSign))
 
 isSep :: Char -> Bool
 isSep c = isSpace c || Set.member c delimiters
diff --git a/parser-typechecker/src/Unison/TermParser.hs b/parser-typechecker/src/Unison/TermParser.hs
index 4a4d368ad..4ff72660b 100644
--- a/parser-typechecker/src/Unison/TermParser.hs
+++ b/parser-typechecker/src/Unison/TermParser.hs
@@ -16,7 +16,6 @@ import           Control.Monad.Reader (asks, local)
 import           Data.Foldable (asum)
 import           Data.Functor
 import           Data.Int (Int64)
-import           Data.List (elem)
 import           Data.Maybe (isJust, fromMaybe)
 import           Data.Word (Word64)
 import           Prelude hiding (and, or, seq)
@@ -525,10 +524,11 @@ number'
   -> P v a
 number' i u f = fmap go numeric
  where
-  go num@(L.payload -> p) | '.' `elem` p    = f (read <$> num)
-                          | take 1 p == "+" = i (read . drop 1 <$> num)
-                          | take 1 p == "-" = i (read <$> num)
-                          | otherwise       = u (read <$> num)
+  go num@(L.payload -> p) | any (\c -> c == '.' || c == 'e') p && take 1 p == "+" = f (read . drop 1 <$> num)
+                          | any (\c -> c == '.' || c == 'e') p                    = f (read <$> num)
+                          | take 1 p == "+"                                       = i (read . drop 1 <$> num)
+                          | take 1 p == "-"                                       = i (read <$> num)
+                          | otherwise                                             = u (read <$> num)
 
 tupleOrParenthesizedTerm :: Var v => TermP v
 tupleOrParenthesizedTerm = label "tuple" $ tupleOrParenthesized term DD.unitTerm pair
diff --git a/parser-typechecker/tests/Unison/Test/Lexer.hs b/parser-typechecker/tests/Unison/Test/Lexer.hs
index 92af140d6..5a8f173c3 100644
--- a/parser-typechecker/tests/Unison/Test/Lexer.hs
+++ b/parser-typechecker/tests/Unison/Test/Lexer.hs
@@ -12,6 +12,44 @@ test =
       , t "-1"   [Numeric "-1"]
       , t "-1.0" [Numeric "-1.0"]
       , t "+1.0" [Numeric "+1.0"]
+
+      , t "1e3"     [Numeric "1e3"]
+      , t "1e+3"    [Numeric "1e+3"]
+      , t "1e-3"    [Numeric "1e-3"]
+      , t "+1e3"    [Numeric "+1e3"]
+      , t "+1e+3"   [Numeric "+1e+3"]
+      , t "+1e-3"   [Numeric "+1e-3"]
+      , t "-1e3"    [Numeric "-1e3"]
+      , t "-1e+3"   [Numeric "-1e+3"]
+      , t "-1e-3"   [Numeric "-1e-3"]
+      , t "1.2e3"   [Numeric "1.2e3"]
+      , t "1.2e+3"  [Numeric "1.2e+3"]
+      , t "1.2e-3"  [Numeric "1.2e-3"]
+      , t "+1.2e3"  [Numeric "+1.2e3"]
+      , t "+1.2e+3" [Numeric "+1.2e+3"]
+      , t "+1.2e-3" [Numeric "+1.2e-3"]
+      , t "-1.2e3"  [Numeric "-1.2e3"]
+      , t "-1.2e+3" [Numeric "-1.2e+3"]
+      , t "-1.2e-3" [Numeric "-1.2e-3"]
+      , t "1E3"     [Numeric "1e3"]
+      , t "1E+3"    [Numeric "1e+3"]
+      , t "1E-3"    [Numeric "1e-3"]
+      , t "+1E3"    [Numeric "+1e3"]
+      , t "+1E+3"   [Numeric "+1e+3"]
+      , t "+1E-3"   [Numeric "+1e-3"]
+      , t "-1E3"    [Numeric "-1e3"]
+      , t "-1E+3"   [Numeric "-1e+3"]
+      , t "-1E-3"   [Numeric "-1e-3"]
+      , t "1.2E3"   [Numeric "1.2e3"]
+      , t "1.2E+3"  [Numeric "1.2e+3"]
+      , t "1.2E-3"  [Numeric "1.2e-3"]
+      , t "+1.2E3"  [Numeric "+1.2e3"]
+      , t "+1.2E+3" [Numeric "+1.2e+3"]
+      , t "+1.2E-3" [Numeric "+1.2e-3"]
+      , t "-1.2E3"  [Numeric "-1.2e3"]
+      , t "-1.2E+3" [Numeric "-1.2e+3"]
+      , t "-1.2E-3" [Numeric "-1.2e-3"]
+
       , t "1-1" [Numeric "1", simpleSymbolyId "-", Numeric "1"]
       , t "1+1" [Numeric "1", simpleSymbolyId "+", Numeric "1"]
       , t "1 +1" [Numeric "1", Numeric "+1"]
diff --git a/parser-typechecker/tests/Unison/Test/TermParser.hs b/parser-typechecker/tests/Unison/Test/TermParser.hs
index 3afcc9d6f..33513bf81 100644
--- a/parser-typechecker/tests/Unison/Test/TermParser.hs
+++ b/parser-typechecker/tests/Unison/Test/TermParser.hs
@@ -22,8 +22,29 @@ test1 = scope "termparser" . tests . map parses $
   , "1.0"
   , "+1"
   , "-1"
+  , "+1.0"
   , "-1.0"
-  , "4th"
+
+  , "1e3"
+  , "1e+3"
+  , "1e-3"
+  , "+1e3"
+  , "+1e+3"
+  , "+1e-3"
+  , "-1e3"
+  , "-1e+3"
+  , "-1e-3"
+  , "1.2e3"
+  , "1.2e+3"
+  , "1.2e-3"
+  , "+1.2e3"
+  , "+1.2e+3"
+  , "+1.2e-3"
+  , "-1.2e3"
+  , "-1.2e+3"
+  , "-1.2e-3"
+
+  , "-4th"
   , "()"
   , "(0)"
   , "forty"