# reacherhq/check-if-email-exists

> A Rust tool that checks whether an email address exists without sending any email: validates syntax, MX records, SMTP, disposable addresses and breaches. Available as a CLI, Docker HTTP backend and Rust library.

- Magnitude: 1.4 out of 10 — Steady
- Stars: 10,089 total · +3 stars on 2026-10-04 (UTC), ≈ 7 by evening
- Star trust: star growth looks organic
- Category: Developer tools · Language: Rust · Created: 2017-04-25 · Last push: 2026-10-02
- GitHub: https://github.com/reacherhq/check-if-email-exists · Homepage: https://reacher.email · Page: https://gitnova.dev/en/r/reacherhq/check-if-email-exists

## Useful for

- Validate signup form email addresses before sending a newsletter
- Run the Docker HTTP backend and call it from your own service
- Filter out disposable and role accounts when accepting signups

## Why it’s here

- 3 stars so far today, about 7 expected by the end of the day.

## Star trust

Star growth looks organic.

Star-trust labels are heuristics based on the repository’s behavior, not a check of every stargazer.

## Numbers

- Forks: 739
- Issues and pull requests: 1,628
- Watchers: 67
- Average over the last week: 10 per day
- Usual pace: 19 per day
- Latest release: v0.11.7 (2026-01-15)

## Stars per day, last 30 days (oldest → newest, today is partial)

2026-09-30 … 2026-10-29: 12, 7, 6, 8, 3, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None

## Magnitude by day, last 14 days

09-21 1.3, 09-22 2.3, 09-23 2.2, 09-24 1.7, 09-25 1.8, 09-26 1.8, 09-27 1.3, 09-28 1.4, 09-29 1.4, 09-30 1.6, 10-01 1.5, 10-02 1.3, 10-03 1.3, 10-04 1.4

---

Magnitude (0–10) measures how fast and how unusually interest in a repository is growing right now. It is not a quality score.
Days are UTC. “So far today” is a fact; “expected by the end of the day” is a forecast.
Summaries and use cases are written by an LLM (DeepSeek V4.1 Flash) from the README and may be inaccurate: verify specific claims (benchmarks, speed, hardware) in the repository itself.
Data as of 2026-10-04 11:02 UTC, updated every 30 minutes.