Django has truncatewords template tag, which cuts the text at the given word count. But there is nothing like truncatechars.
truncatewords
What\'s the best w
You should write a custom template filter: http://docs.djangoproject.com/en/dev/howto/custom-template-tags/#writing-custom-template-filters
Have a look at how truncatewords is built in django.utils.text
django.utils.text