Alternatives to ImprovMX

ImprovMX: Email forwarding for custom domains, with SMTP sending and a JSON send API. 8 products similar to ImprovMX, compared on pricing, free tier, API, MCP server, SDK and open source. 8 of 8 have a free tier, 6 of 8 have an API, 2 of 8 offer an MCP server, 3 of 8 are open source.

KaiMail
Email forwarding for custom domains
Email & messaging free tierAPI
Forward Email
Free email forwarding for custom domains with open-source email hosting, sending, and a developer API.
Email & messaging free tierAPIMCPopen source
Alias Email
Free email alias service that forwards messages to your main inbox
Email & messaging free tier
SimpleLogin
Open source anonymous email alias service
Email & messaging free tierAPISDKopen source
Resend
Email API for developers
Email & messaging free tierAPIMCPSDK
Imitate Email
Sandbox email server for software teams
Testing & QA free tierAPI
Mutant Mail
Manage multiple email addresses from one inbox with two-way email routing
Email & messaging free tier
addy.io
Open-source anonymous email forwarding with unlimited aliases
Email & messaging free tierAPIopen source

Side by side

Product	Pricing	Free tier	API	MCP server	SDK	Open source
ImprovMX	Freemium · from $9/month	yes	yes	no	—	no
KaiMail	Freemium · from ¥550/month	yes	yes	no	no	—
Forward Email	Freemium · from $3/month	yes	yes	yes	—	yes
Alias Email	Freemium · from $3.33	yes	no	no	no	no
SimpleLogin	Freemium · from $4/month (Premium, billed monthly) or $36/year; Free plan with 10 aliases	yes	yes	no	yes	yes
Resend	Freemium	yes	yes	yes	yes	no
Imitate Email	Freemium · from $7/mo	yes	yes	no	no	no
Mutant Mail	Freemium	yes	no	no	no	no
addy.io	Freemium · from $1/month (Lite, billed yearly); Pro $3/month billed yearly or $4/month billed monthly; Duo $4.50/month; Family $7.50/month	yes	yes	no	no	yes

Facts come from each product's own website, or from its verified owner when they have edited the listing. Each product page shows when it was last verified and how it was extracted. Similarity comes from the products' descriptions.

API

curl https://toolgrep.com/api/products/improvmx/alternatives