CyberTemp vs Mail.tm: API-first temp mail compared in 2026

If you're picking between CyberTemp and Mail.tm for an automated signup flow, an OTP test in CI, or any pipeline that needs to read incoming mail without a real address, here's the short version: Mail.tm is the right call if you want a fully-free API with no concept of tiers at all and 8 QPS per IP is enough for your traffic. CyberTemp is the right call if you want per-key quotas, persistent API keys, official SDKs, OTP extraction built in, and a paid tier when you outgrow the free one.

Both are real, working, API-first temp mail services. Neither is a knockoff of the other. They take different shapes, and which one fits depends on the constraints of the system you're putting them in.

This continues the same comparison thread we ran in CyberTemp vs DraxonMails earlier this month. Mail.tm sits in a different lane than DraxonMails though. It's API-first like CyberTemp, with no operator dashboard ambition and no subscriber framing, so the comparison is much closer to apples-to-apples.

Mail.tm: how it works in 2026

Mail.tm is a free, advertising-supported temp mail service with a documented public API at api.mail.tm. The model is account-based: every inbox is an account with a password you choose, and you exchange those for a short-lived bearer token before reading mail.

The minimum sequence to read your first message looks like this:

GET  https://api.mail.tm/domains
POST https://api.mail.tm/accounts
     body: { "address": "[email protected]", "password": "your-password" }
POST https://api.mail.tm/token
     body: { "address": "...", "password": "..." }
GET  https://api.mail.tm/messages
     header: Authorization: Bearer <jwt-from-token>

Three calls of setup, then a read call. The bearer is a JWT that eventually expires, so a long-running worker either keeps it warm or runs the /token exchange again. The password is something you choose at account creation, and you'll need it again any time you want a fresh bearer for the same address. Lose the password, lose the inbox.

Rate limiting is the headline detail worth pinning to memory: 8 queries per second per IP address. That's per-IP, not per-account, so multiple workers behind the same NAT or shared cloud egress all draw from the same budget. Mail.tm itself says the service is "completely free" with no API key and no paid tier — there is no upgrade path if 8 QPS or the default rate budget stops being enough.

There are no official SDKs published by the Mail.tm team. Community client libraries exist on npm and PyPI, but their maintenance is uneven and the API surface they wrap is whatever the author found useful at the time. For anything beyond a hobby script you'll be writing the HTTP calls yourself or auditing a community wrapper before trusting it.

CyberTemp: how it works in 2026

CyberTemp's API lives at api.cybertemp.xyz. The auth model is a persistent per-user API key sent as a header: generate one in the dashboard, paste it into your script, and it stays valid until you rotate it.

The minimum sequence to read your first message:

GET https://api.cybertemp.xyz/[email protected]
    header: X-API-Key: tk_...

That's the whole setup. The first call to GET /getMail for an address that doesn't exist yet creates the inbox on the spot and returns an empty array. Subsequent calls return whatever has arrived since, most recent first. The address belongs to your API key, and the key itself stays valid until you rotate it in the dashboard.

Rate limits are tied to the API key, not the IP. That matters for anyone running CI workers, a fleet of containers behind a single egress, or a small team sharing one corporate IP. Your quota travels with your key, not your network location.

The free tier is real and usable. Paid tiers exist for higher inbox counts, higher rate limits, and helpers like WaitForOTP, which regex-extracts a 4–8 digit code from incoming mail and returns it as soon as one arrives. That last one is the difference between writing a 4-line OTP call and writing a poll loop with a custom regex per service. Official SDKs are published in Go and Rust by the same team that runs the API. Python is hand-rollable against the raw endpoints with requests or httpx.

Where they actually differ

Both services solve the same surface-level problem: get an inbox, read mail, throw it away. The differences show up once either of them is sitting inside a real automated flow:

Setup-call count. Mail.tm needs three calls before mail can be read (/domains, /accounts, /token). CyberTemp's first GET /getMail is the create-and-read in one step.
Auth model. Mail.tm hands you a JWT that needs refreshing. CyberTemp's X-API-Key is persistent.
Rate budget. Mail.tm: 8 QPS per IP. CyberTemp: per-key. If multiple workers run behind one IP, those Mail.tm calls all share the same 8 QPS budget; CyberTemp's quota is yours alone regardless of where the requests originate.
Tiers. Mail.tm has none — what you see is what you get. CyberTemp has a free tier plus paid tiers for higher limits, more concurrent inboxes, and the OTP-extraction helper.
OTP-specific behavior. Mail.tm gives you the message; you parse the code yourself. CyberTemp's Pro WaitForOTP returns the code directly once a matching message arrives, with a single timeout-bounded call.
SDKs. Mail.tm: community-maintained, variable quality. CyberTemp: official Go and Rust SDKs from the team that runs the API, with versioned releases.
Account recovery model. Mail.tm couples inboxes to a password you chose at account creation. CyberTemp ties inboxes to your API key. Losing one vs losing the other is a different blast radius.

What both services do well

It would be dishonest to write this comparison without naming what both do right. Both services:

Run a real, documented, public JSON API — not a screen-scraped frontend pretending to be one.
Return mail in machine-readable form (no HTML body parsing of a web inbox required).
Treat inboxes as cheap and disposable rather than as user accounts with onboarding ceremony.
Publish their domain list so you can pick or rotate sender domains for signup-flow testing.
Stay out of your way once you've made the first call work.

If you're coming from the legacy free temp-mail world — the kind of service where you check a public web inbox by typing the address into a form — either of these is a step-change in what's possible. The choice is which set of constraints you'd rather work inside.

The honest tradeoff

Mail.tm's offer is genuinely simple: free, no tier you can outgrow, entire surface documented in one place. If you're scripting signups on a personal project, doing one-off email research, or you just don't want to deal with a billing relationship, Mail.tm is a fine choice and we'd cheerfully tell you so. We're not here to claim otherwise.

The places where Mail.tm shows its limits are at scale and at the edges. 8 QPS per IP is a real ceiling when CI runners share an egress. The token-refresh becomes a thing you maintain. The lack of OTP-extraction means more parsing code in every project — and that's the code that breaks first when a new SaaS changes the format of its verification email. There's no upgrade path when free isn't enough; the move at that point is a switch to a different service, not a plan change.

CyberTemp's bet is that most people building against a temp mail API will eventually want one or more of: more inboxes, higher rate limits, OTP extraction without writing parsers, or a relationship with the people running the service. The free tier is there for the learning-and-prototyping phase. The paid tiers on /pricing are there for the part where it has to work in production at predictable cost.

A related but separate concern — neither service should be your strategy for personal email privacy. Temp mail is for signups, throwaway accounts, and verification flows, not for routing email you actually need to keep. We wrote about that distinction in how temporary email actually protects your privacy.

Who should pick which one?

Pick Mail.tm if your traffic is low, you genuinely want zero billing relationship, 8 QPS per IP is enough for your workload, and you're comfortable maintaining the token exchange and writing your own OTP parsing.

Pick CyberTemp if you want per-key rate limits that travel with the credential instead of the IP, persistent API keys that stay valid until you rotate them, official SDKs from the team that runs the service, OTP extraction built into the API on the Pro tier, and a clear upgrade path when the free tier stops being enough.

Same shape of problem. Different shape of solution. The point isn't that one of these services is bad — it's that they're solving for different users. Pick the one whose constraints match yours and don't pay for things you don't need.