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Mail.cx

mail.cx

From $0.82/mo Free plan WebAPI
Visit mail.cx
Spec score 9.1 #4 of 44 in Temporary email services

What it is

Mail.cx provides short-lived inboxes for developers, QA teams, and product teams checking account verification, transactional messages, notification pipelines, or application integrations. It only receives email; it does not send it. A web inbox can be opened without signup by choosing a username or generating one, and server-sent events can push arriving mail to the browser. Its REST API supports long-polling, retrieval of parsed or raw email, attachment downloads, and event delivery. API use is limited to 10 requests per second per token; long-polling allows one concurrent wait per token and 10 per address. Free messages are automatically deleted after one hour, while Pro messages are retained for 72 hours. The Free plan is free, and Pro is $9.90 a year. A separate pricing note lists paid plans from $4/mo. Mail.cx says connections use TLS and that passwords and API tokens are stored as hashes. Its terms caution that message retention and recovery are not guaranteed, and advise against relying on the service for critical, sensitive, or business-essential communications.

Spec sheet

What it does
Mail.cx provides short-lived email inboxes for receiving messages and testing email workflows.Read 19 Oct 2026 · mail.cx
Product
Mail.cx provides short-lived inboxes, email receiving, API access, and real-time mailbox events for developer workflows.Read 29 Sep 2026 · mail.cx
API
The REST API supports long-polling inboxes, retrieving parsed or raw email, downloading attachments, and server-sent event delivery.Read 29 Sep 2026 · mail.cx
Security
Mail.cx says connections use TLS, passwords are hashed with bcrypt, and API tokens are stored as SHA-256 hashes.Read 29 Sep 2026 · mail.cx
Privacy
The privacy policy says inbox content, account email, and API tokens are not sold, rented, or shared with advertisers or other third parties.Read 29 Sep 2026 · mail.cx
Support
The contact page says support normally responds within two business days and prioritizes security and abuse reports.Read 19 Oct 2026 · mail.cx
Advertising boundary
The inbox, message-reading view, dashboard and authentication screens do not load advertising scripts, while selected marketing pages may show Google AdSense.Read 19 Oct 2026 · mail.cx
API attachments
Individual email attachments can be downloaded by zero-based attachment index.Read 19 Oct 2026 · mail.cx
API base
The REST API uses https://api.mail.cx/v1 and authenticates with an x-api-token header.Read 19 Oct 2026 · mail.cx
API domain management
API endpoints allow adding, listing and deleting custom domains and checking verification status.Read 19 Oct 2026 · mail.cx
API hold time
Long-poll requests remain open for a server-fixed maximum of 25 seconds.Read 19 Oct 2026 · mail.cx
API inbox endpoint
The API supports long-polling inbox retrieval with cursor-based since parameters.Read 19 Oct 2026 · mail.cx
API limits
The API allows 10 requests per second per token; long-polling is limited to one concurrent wait per token and 10 per address.Read 29 Sep 2026 · mail.cx
API message formats
Developers can retrieve parsed text, HTML and attachments or download the original .eml stream.Read 19 Oct 2026 · mail.cx
API rate limits
Pro API tokens are limited to 10 requests per second, one concurrent long-poll per token and ten per address.Read 19 Oct 2026 · mail.cx
API SSE
The API offers server-sent event endpoints for one address or all owned addresses.Read 19 Oct 2026 · mail.cx
API token management
Tokens can be created, listed and revoked through API endpoints, with plaintext shown only at creation.Read 19 Oct 2026 · mail.cx
Automatic deletion
Messages and inbox data are automatically deleted when the applicable retention period ends.Read 19 Oct 2026 · mail.cx
Custom domains
Pro users can connect up to 100 custom domains using DNS verification.Read 19 Oct 2026 · mail.cx
Custom usernames
Users may choose their own local part or have one generated randomly.Read 19 Oct 2026 · mail.cx
Dedicated domains
The Pro plan includes dedicated system domains in addition to public domains.Read 19 Oct 2026 · mail.cx
External associated-domain count
Check-Mail reports fewer than 100 domains associated with mail.cx and says the newest was added five days earlier when checked.Read 19 Oct 2026 · check-mail.org
External classification
Check-Mail classifies mail.cx as a temporary-email provider and recommends blocking associated domains at signup to prevent abuse.Read 19 Oct 2026 · check-mail.org
External detection
Check-Mail says its API detects and blocks mail.cx domains in real time, including newly appearing domains.Read 19 Oct 2026 · check-mail.org
External domain age
HypeStat reported that the mail.cx domain was created on January 29, 2016 and registered through CentralNic.Read 19 Oct 2026 · hypestat.com
External hosting
HypeStat resolved mail.cx through Cloudflare IP addresses and ASN AS13335.Read 19 Oct 2026 · hypestat.com
External HTTPS status
HypeStat reported that mail.cx supports HTTPS and has a certificate for *.mail.cx.Read 19 Oct 2026 · hypestat.com
External technology detection
HypeStat detected Cloudflare, Google AdSense and HTTP/3 on mail.cx.Read 19 Oct 2026 · hypestat.com
External traffic estimate
HypeStat estimated about 124 daily visitors and 170 daily page impressions for mail.cx.Read 19 Oct 2026 · hypestat.com
External traffic rank
HypeStat listed mail.cx at approximately global rank 5,363,878.Read 19 Oct 2026 · hypestat.com
Free retention
Free-plan mail is retained for one hour.Read 19 Oct 2026 · mail.cx
Inbox creation
Users can pick a username or generate one randomly, and the web inbox is available without signup.Read 29 Sep 2026 · mail.cx
Operator
Mail.cx identifies SICHUAN HAONI E-COMMERCE CO., LTD. as its operator.Read 19 Oct 2026 · mail.cx
Password protection
Passwords are stored using bcrypt hashes.Read 19 Oct 2026 · mail.cx
Pricing change
A September 24, 2026 announcement states that API access changed from free to $9.9 per year while the website remained free.Read 19 Oct 2026 · mail.cx
Pro retention
Pro-plan mail is retained for 72 hours.Read 19 Oct 2026 · mail.cx
Real-time delivery
Server-sent events push newly received messages to the browser immediately.Read 19 Oct 2026 · mail.cx
Receive-only
The service receives email but does not provide email-sending functionality.Read 19 Oct 2026 · mail.cx
Refund policy
The first Pro payment has a 15-day money-back guarantee, while renewal payments are non-refundable.Read 19 Oct 2026 · mail.cx
Retention
Mail is kept for 1 hour on Free and 72 hours on Pro, then automatically deleted.Read 29 Sep 2026 · mail.cx
Retention limitation
The terms warn that message recovery and long-term storage are not guaranteed and advise against critical communications use.Read 19 Oct 2026 · mail.cx
Security transport
Mail.cx states that connections are encrypted with TLS.Read 19 Oct 2026 · mail.cx
Service availability limitation
The terms disclaim uninterrupted availability, error-free operation and permanent access to features.Read 19 Oct 2026 · mail.cx
Service limitation
The terms say the service does not guarantee message retention or recovery and should not be relied on for critical, sensitive, or business-essential communications.Read 29 Sep 2026 · mail.cx
Team disclosure
The contact page describes the operator as a small remote team without a public walk-in office.Read 19 Oct 2026 · mail.cx
Temporary addresses
Users can instantly generate a disposable address without registration or payment.Read 19 Oct 2026 · mail.cx
Token protection
API tokens are stored as SHA-256 hashes rather than plaintext.Read 19 Oct 2026 · mail.cx
Use cases
Mail.cx targets developers, QA teams and product teams testing verification, transactional email, notifications and application integrations.Read 19 Oct 2026 · mail.cx

Plans and prices

Free Free Web inbox · 1-hour mail retention · no signup required Read 29 Sep 2026 · mail.cx
Free Free real-time delivery · public system domains · 1-hour mail retention · no signup · rate-limited web inbox Read 19 Oct 2026 · mail.cx
Pro $9.90 a year $9.9 per year Custom domains · dedicated system domains · API access · 72-hour mail retention Read 29 Sep 2026 · mail.cx
Pro $9.90 a year $9.9/year 72-hour retention · up to 100 custom domains · dedicated system domains · up to 100 API keys · 10 requests/second · unlimited web inbox without free-plan limits Read 19 Oct 2026 · mail.cx

Every Mail.cx plan and price →

Strong points and limits

Strong points

  • Web inboxes require no signup.
  • Supports parsed and raw email retrieval.
  • API can download attachments.
  • Pro retains mail for 72 hours.

Limits

  • Does not provide email sending.
  • Free messages last one hour.
  • API traffic is limited to 10 requests per second per token.
  • Terms advise against relying on it for critical communications.

Who it suits

Mail.cx suits developers and QA or product teams testing email flows rather than sending messages. Its short retention window makes it a poor fit for communications that must be preserved.

Verdict

Mail.cx offers inboxes and API tools for temporary email testing, with explicit rate and retention limits. Do not rely on it for critical or sensitive communications.

Where Specifiction places it

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