pypi / wtforms

wtforms

What changed in wtforms 3, from its official release notes, upgrade guides and advisories. Sources checked 2026-10-25.

2 breaking1 deprecations10 new APIs and options1 performance6 behavior and defaults13 fixes and other

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npx @unstale/cli init

wtforms 333 changes

Render-time checked kwargs take precedence over field.checked.
3.3.0release notes
Radio labels no longer render a for attribute.
3.3.0release notes

ButtonField is implemented.
3.3.0release notes
Datalist is implemented.
3.3.0release notes
A DateRange validator, similar to NumberRange, is implemented.
3.3.0release notes
DateTimeLocalField accepts a tz parameter.
3.3.0release notes
The Email validator supports test_environment.
3.3.0release notes
Error messages can be customized.
3.3.0release notes
The formdata parameter is passed to post_process.
3.3.0release notes
RangeInput implements min and max parameters.
3.3.0release notes
The Regexp validator allows customization of its match method.
3.3.0release notes
SelectField supports Enum choices, with improved enum coercion and backward compatibility.
3.3.0release notes

Choices callables are resolved lazily.
3.3.0release notes
FloatField uses NumberInput by default.
3.3.0release notes
html_params returns Markup.
3.3.0release notes
ListField uses Meta.bind_field instead of the default bind method.
3.3.0release notes
The URL validator accepts user/password and uses urllib.urlparse.
3.3.0release notes
The UUID validator accepts uuid.UUID objects.
3.3.0release notes

FieldList keeps the form prefix when renumbering its entries.
3.3.1release notes
Choice and SelectChoice dataclasses are re-introduced.
3.3.0release notes
The Email validator respects email_validator default values.
3.3.0release notes
post_process is appended on new FieldList items.
3.3.0release notes
FieldList resets index state when process is called, handles entries with indices, and uses consecutive IDs after insert and remove.
3.3.0release notes
Double quotes in HTML attribute values are escaped.
3.3.0release notes
Numeric fields handle TypeError.
3.3.0release notes
WTForms supports Python 3.15.
3.3.0release notes
The Regexp validator sets the HTML input pattern attribute.
3.3.0release notes
render_kw is copied for each form instance.
3.3.0release notes
False values are handled correctly with Select.
3.3.0release notes
Supports Python versions from 3.10 to 3.14.
3.2.2release notes
Fixes validation being disabled when formdata is provided.
3.2.2release notes