mailchecker
Cross-language temporary email detection library. Stop users from signing up with temporary email addresses.
What it is and what it does
MailChecker is a cross-language email validation library that performs two checks: format validation (using standard email regex patterns) and temporary email detection (by checking against a curated database of over 55,000 known disposable email domains). It helps prevent sign-ups and communications with throwaway email services like Yopmail and similar providers.
The package is designed for developers who need to filter out temporary email addresses during user registration or contact workflows. It has no runtime dependencies, installs quickly, and provides a simple API: call `MailChecker.is_valid()` with an email string and receive a boolean result. The underlying domain list is maintained by the project maintainers and can be extended by contributors.
Use it for:
- Block temporary email addresses during user registration to ensure valid contact information.
- Filter out disposable emails from mailing lists before sending campaigns to reduce bounce rates.
- Validate email format and reject known spam-box domains in contact forms.
- Pre-screen user signups to avoid wasted communication attempts with non-functional addresses.
- Integrate email validation into data import pipelines to catch bad addresses early.
Worth the install?
AI-flagged interpretation of the facts on this page — verify before relying
Validates email addresses against format rules and checks whether they belong to temporary/throwaway email services using a database of over 55,000 known disposable domains.
Yes. The package solves a real problem with zero dependencies, permissive licensing, active maintenance, and a straightforward API. Use it when you need to reject temporary email addresses during signup or contact workflows. The only caveat is verifying that the throwaway domain database stays current for your use case.
Install
mailchecker on PyPI
pip
pip install mailcheckeruv
uv add mailcheckerpoetry
poetry add mailcheckerInstalling mailchecker
Before you install
Low friction installation with no runtime dependencies. The package is actively maintained with a recent release (26 days ago) and has accumulated 1901 repository stars, indicating stable, long-term support.
License in practice
Licensed under MIT (permissive), so you can use it freely in commercial and open-source projects without restriction or attribution requirement.
Quickstart
pip install mailchecker
from MailChecker import MailChecker
if not MailChecker.is_valid('bla@example.com'):
print("Invalid email")
Requires Python 3.6 or later.
Verify before relying
- Whether the throwaway domain database is updated automatically or requires manual maintenance.
- Performance characteristics when validating large batches of emails.
- Exact regex used for format validation and how it compares to RFC 5322 compliance.
Package facts
| License | not declared (permissive) |
| Python support | supports the current Python release (>=3.6) |
| Install friction | low — pure-Python wheel |
| Runtime dependencies | none |
| Maintenance | actively maintained — 26 days since the last release |
| Last repo commit | |
| First released | |
| Downloads | 588,383/month — #5,868 on PyPI (30-day window, as of 2026-08-14) |
| Known vulnerabilities | none known (OSV.dev, checked 2026-08-14) |
Evidence: mailchecker-6.0.21-py3-none-any.whl
Tags
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