Maski vs addy.io: unlimited has a footnote

addy.io is a good piece of software made by someone who clearly cares. It is open source, the paid tier starts at a dollar a month, and it gives you more knobs than anything else in this comparison. Three sentences in and I have already conceded price, licence and depth.

What I want to talk about is the word unlimited, because addy.io uses it and then puts a footnote on it, and the footnote is the part that decides whether you like the product.

Two different bets about what to meter

addy.io meters bandwidth. You get unlimited standard aliases on every tier, including free, and their FAQ adds the qualifier in their own brackets: within your monthly bandwidth limit. That limit is ten megabytes a month on the free plan. Forwarded mail counts against it. So do replies.

Ten megabytes is not a lot of email. It is a few dozen plain newsletters, or one invoice with a PDF attached, repeated a handful of times. Unlimited aliases inside a ten megabyte pipe is a real offer, but it is an offer about aliases, not about mail.

Maski meters aliases and meters sends, and does not meter bytes. You get a fixed number of addresses and a daily forward count, and a large attachment costs you nothing extra. I think counting messages is easier to reason about than counting megabytes, mostly because you can predict it. Nobody knows how big their email is.

What matters, side by side

Maski compared with addy.io on price, aliases included, custom domains, replying to a forwarded message, and sending a new message from the alias.
Compared on	Maski	addy.io
Price	Free, or $4.99 a month for Pro Buys the alias service itself. No mailbox or storage is bundled in. Pro is free for a year for the first 1,000 sign-ups.	Free, or $1 a month for Lite billed yearly Buys the alias service. Pro is $3 a month billed yearly. Their page prints a bare $ with no currency code. Pricing — addy.io, opens in a new tab
Aliases included	10 on Free, 25 on Pro	Unlimited on your own addy.io subdomain; 10 / 50 / unlimited on shared domains Their FAQ qualifies unlimited as within your monthly bandwidth limit: 10 MB a month on free. Pricing — addy.io, opens in a new tab FAQ — addy.io, opens in a new tab
Custom domains	Yes, on Pro Bring your own domain. Maski can publish the DNS records for supported providers.	None on the free plan, 1 on Lite, 20 on Pro Bring your own domain. Pricing — addy.io, opens in a new tab
Reply to a forwarded message	Yes, on Pro The alias stays in the From address. Your real address is never disclosed to the sender.	Paid plans only Free-plan replies are not delivered; you get a notification instead. FAQ — addy.io, opens in a new tab
Send a new message from the alias	Yes, on Pro You compose in your own mail client and address the message through Maski, so the alias is the sender.	Paid plans only Shares a daily limit with replies: 50 on Lite, 200 on Pro. Pricing — addy.io, opens in a new tab FAQ — addy.io, opens in a new tab

Verified 11 September 2026. I re-check every figure on its source page, and this date only moves when the whole table has been checked again.

The free plan cannot answer anybody

On addy.io, replying and sending from an alias are paid features. Their FAQ is specific about what happens if you try it on the free plan: the message will not be delivered and you get a notification telling you the feature needs a paid plan.

That is the correct way to handle it and I am not criticising the design. I am pointing out that a forwarding-only address is a different product from an address you can hold a conversation through, and the free tier is the first one.

Maski gates replying behind Pro too. Same wall, different side of it, and you should check which features sit on the free side of each before you pick.

Knobs are a cost, not only a feature

addy.io splits aliases into standard ones on your own addy.io subdomain and shared domain ones, with different limits for each. There is a creation rate cap per hour. There is a bandwidth cap per month. There is a separate daily cap on replies and sends.

Every one of those is defensible on its own and all four are published, which is more than most of this field manages. But four interacting limits is a thing you have to hold in your head, and the moment mail stops arriving you have four places to check.

This is a taste argument, not a correctness one. If you like the knobs, that is a real reason to prefer addy.io and I do not think you are wrong.

What Maski spends its complexity on instead

Per-sender rules. One alias, several senders, and a decision for each: forward, block, or hold it in a Maski inbox so it never reaches your real one. The retailer keeps working, the list broker who bought your address does not.

And a one-click pause wired into the unsubscribe header of the mail itself, so shutting a sender up is the same gesture as unsubscribing, except the sender is never told you exist.

BE HONEST: when addy.io is the right call

A dollar a month. Lite is $1 a month billed yearly. Maski Pro is $4.99 a month, free for the first year if you are one of the first 1,000 sign-ups. After that year there is no argument I can make that closes the gap, and if budget is the constraint then this is over.

It is open source and Maski is not. Their code is public. My repository is private. That is a genuine difference in what you can verify about the thing handling your mail, and it is not in my favour.

They publish a custom domain number. One on Lite, twenty on Pro, printed on the pricing page. Maski does not publish a per-plan count anywhere a customer can read it, and that is a fair thing to hold against it until it does.

Unlimited aliases really is unlimited. If you are the kind of person who makes a new address for every single signup and your mail is mostly text, the bandwidth cap may never touch you, and then you are getting an enormous amount for nothing.

Is one of those the reason you would not switch?

Then tell me which one. If the thing keeping you on addy.io is a feature I do not have yet, I would rather hear it from you than guess at it, and a short note saying what you need and what you are using it for is worth more to me than any amount of competitor research.

Write to jay@maski.dev and it comes to me. If you would rather it went to the support queue, use hey@maski.dev. I cannot promise to build everything, and I will not pretend otherwise, but nothing gets built that nobody asked for.

Try it on the sender you cannot block today

Pick the address that gets the worst mail. Point the next signup at a Maski alias instead, and block the first sender that misbehaves without touching the other three. Free plan, no card.

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