diff --git a/cps/helper.py b/cps/helper.py
index 722a6245..5aaeb988 100755
--- a/cps/helper.py
+++ b/cps/helper.py
@@ -108,6 +108,65 @@ def send_registration_mail(e_mail, user_name, default_password, resend=False):
                                   e_mail, user_name, _(u"Registration e-mail for user: %(name)s", name=user_name),text)
     return
 
+def chk_send_to_kindle(book_id):
+    '''
+        Used to determine if we can show the Send to Kindle button.
+        Specifically checks the existing book formats and the conversion options available.
+
+        mobi = true
+        epub && kindlegen or ebookconvert = true
+        all valid 'book' format && ebookconvert = true
+        all other combinations = false
+    '''
+    book = db.session.query(db.Books).filter(db.Books.id == book_id).first()
+    data = db.session.query(db.Data).filter(db.Data.book == book.id).all()
+    if data:
+        bookformats = get_formats_from_book(data)
+
+        if ub.config.config_ebookconverter == 0:
+            # no converter - only allow for mobi and pdf formats
+            if 'MOBI' in bookformats or 'PDF' in bookformats:
+                return True
+            else:
+                return False
+        else:
+            if ub.config.config_ebookconverter == 1:
+                # the converter is kindlegen - only allow epub
+                if 'EPUB' in bookformats:
+                    return True
+                else:
+                    return False
+            
+            if ub.config.config_ebookconverter == 2:
+                # the converter is ebook-convert - allow for any allowable 'book' format
+                formatcount = 0
+                for bookformat in bookformats:
+                    if bookformat.lower() in web.EXTENSIONS_CONVERT:
+                        formatcount += 1 
+                
+                if formatcount > 0: 
+                    return True
+                else:
+                    return False
+            else:
+                return False
+
+        return False    
+    else:
+        app.logger.error(u'Cannot find book entry %d', book_id)
+        return False
+
+def get_formats_from_book(data):
+    '''
+        data s/b the data member of db.entry
+        returns a list of formats
+    '''
+    formatlist=[]
+    for entry in data:
+        formatlist.append(entry.format.upper())
+
+    return formatlist
+
 
 # Files are processed in the following order/priority:
 # 1: If Mobi file is exisiting, it's directly send to kindle email,
diff --git a/cps/templates/detail.html b/cps/templates/detail.html
index 420b98a6..0269ad38 100644
--- a/cps/templates/detail.html
+++ b/cps/templates/detail.html
@@ -40,7 +40,7 @@
             </div>
             {% endif %}
           {% endif %}
-            {% if g.user.kindle_mail and g.user.is_authenticated %}
+            {% if g.user.kindle_mail and g.user.is_authenticated and flg_kindle%}
             <a href="{{url_for('send_to_kindle', book_id=entry.id)}}" id="sendbtn" class="btn btn-primary" role="button"><span class="glyphicon glyphicon-send"></span> {{_('Send to Kindle')}}</a>
             {% endif %}
               {% if entry.data|length  %}
diff --git a/cps/web.py b/cps/web.py
index 2d1e5f3f..3673e0aa 100644
--- a/cps/web.py
+++ b/cps/web.py
@@ -1586,9 +1586,11 @@ def show_book(book_id):
 
         entries.tags = sort(entries.tags, key = lambda tag: tag.name)
 
+        flg_send_to_kindle = helper.chk_send_to_kindle(book_id)
+
         return render_title_template('detail.html', entry=entries, cc=cc, is_xhr=request.is_xhr,
                                      title=entries.title, books_shelfs=book_in_shelfs,
-                                     have_read=have_read, page="book")
+                                     have_read=have_read, flg_kindle=flg_send_to_kindle, page="book")
     else:
         flash(_(u"Error opening eBook. File does not exist or file is not accessible:"), category="error")
         return redirect(url_for("index"))
@@ -3846,8 +3848,9 @@ def upload():
                     return render_title_template('book_edit.html', book=book, authors=author_names,
                                                  cc=cc, title=_(u"edit metadata"), page="upload")
                 book_in_shelfs = []
+                flg_send_to_kindle = helper.chk_send_to_kindle(book_id)
                 return render_title_template('detail.html', entry=book, cc=cc,
-                                             title=book.title, books_shelfs=book_in_shelfs, page="upload")
+                                             title=book.title, books_shelfs=book_in_shelfs, flg_kindle=flg_send_to_kindle, page="upload")
     return redirect(url_for("index"))