Where can I find my API key?

Log in to your account at lettr.com and navigate to the API Keys section.

by vojtechj 0 (0 reviews)

Lettr – Email API

Name: Lettr – Email API
Author: vojtechj

Send transactional emails from your site through the Lettr email API.

Lettr ranks #60,077 among WordPress.org plugins with 0+ active installations, is #3,040 of 3,382 in the Communication category, and was last updated Sep 22, 2026. Data from WordPress.org, refreshed twice daily — see methodology.

Tested up to WP 7.0.5 (Current: 7.1.2)

v1.5.0 Current Version v1.5.0

Updated 7 hours ago Last Update on 22 Sep, 2026

Refreshed 12 hours ago Last Refreshed on

#3,040 of 3,382 in Communication Downloads -18.6% this week Actively maintained

View on WordPress.org

Rank

#60,077

-2527 this week

Active Installs

-100%

KW Avg Position

0.5 better

Downloads

391

+28 today

Support Resolved

— No change

Rating

Review 0 out of 5

0 (0 reviews)

Next Milestone 10

Total Progress 20%

0+ 10+

28,410

Ranks to Climb

Growth Needed

8,000,000

Active Installs

Pro

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Need 8 more installs to reach 10+

Rank Changes

Current #60,077

Change

Best #

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Active Installs Growth

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Active Installs 0,000,000+

Growth +0.0%

Peak 0,000,000

Downloads Growth

Downloads

Growth

Peak

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Reviews & Ratings

0.0

0 reviews

Overall 0%

0 (0%)

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Plugin Details

Version: 1.5.0
Last Updated: Sep 22, 2026
Requires WP: 5.8+
Tested Up To: 7.0.5
PHP Version: 7.2 or higher
Author: vojtechj

Support & Rating

Rating: ☆ ☆ ☆ ☆ ☆ 0
Reviews: 0
Support Threads: 0
Resolved: 0%

Keywords

email Email API lettr smtp transactional email

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Frequently Asked Questions

Common questions about Lettr – Email API

Yes. Sign up for free at lettr.com to get your API key.

Yes. Lettr handles all emails sent via the standard WordPress wp_mail() function, which includes WooCommerce order confirmations, shipping notifications, and customer emails.

No. Lettr uses a REST API instead of SMTP, which means there are no ports to open or SMTP credentials to manage.