Email live · SMS & WhatsApp in build

Messages that arrive, priced to the paisa.

Aslio is one API and one prepaid wallet for email, SMS and WhatsApp. Send your first message in a few minutes, watch every delivery outcome, and pay ₹0.02 an email with no monthly fee.

Create a free account Read the API docs

No card required · Wallet starts empty · Top up when you are ready

Request

POST /v1/email/send
Authorization: Bearer as_live_…
Idempotency-Key: invoice-4417

{ "from": "Acme <news@acme.in>",
  "to": ["priya@example.com"],
  "subject": "Your invoice is ready" }

Delivery

QUEUED—
Accepted and charged
SENT—
Handed to the provider
DELIVERED—
Accepted by the recipient's mail server

Wallet

₹500.000000

This message

−₹0.020000

Channels

One integration, four channels

Auth, wallet, logging and webhooks are shared. Adding a channel later means a different endpoint, not a different integration.

Email

Live

Transactional and marketing. DKIM-verified domains, one-click unsubscribe, delivery webhooks.

₹0.02 / message

SMS

In build

India first, with DLT header and template registration handled inside the dashboard.

₹0.25 / segment at launch

In build

Send from your own number with your business name — never a shared one. Optional AI agent answers your customers automatically.

from ₹0.10 / message at launch

Voice

Planned

OTP delivery and call flows, once the messaging channels are settled.

—

From nothing to sending

Three steps, in order

01
Verify a sending domain
Add your domain, publish the three DKIM records we return, and click Check. Mail then sends from your address.
```
POST /v1/senders
{ "type": "domain",
  "value": "acme.in" }
```
02
Top up the wallet
Every message is charged against a prepaid balance. No invoices, no surprise bills, and you can never overspend.
```
GET /v1/account
→ { "balanceMicros":
     "500000000" }
```
03
Send
One POST per message, or up to 1,000 recipients per batch with per-recipient merge variables.
```
POST /v1/email/send
{ "to": ["priya@…"],
  "subject": "Hello" }
```

Built in

The parts you would otherwise write yourself

Most of the work in sending mail is not the sending. It is what happens when a request is retried, a message bounces, or somebody unsubscribes.

Idempotency that actually holds

Send with an Idempotency-Key and retry as often as you like. A duplicate replays the original response instead of sending twice — enforced by a unique index, not a check-then-write race.

You are refunded when we fail

If a message is charged and then permanently fails, the wallet is credited back automatically and the key is released so your retry can succeed.

Suppression is enforced before billing

Hard bounces and complaints add the address to your do-not-mail list. Later sends to it are rejected before you are charged, which protects your sender reputation and ours.

One-click unsubscribe, built in

Marketing sends carry RFC 8058 headers, so Gmail and Yahoo show a native Unsubscribe button. Required for bulk senders since 2024.

Delivery pushed to you

Give us a statusCallbackUrl and every outcome is POSTed to you, HMAC-signed. No polling loop to write.

Verify your own domain

Add a sender, publish the DKIM records we return, and check verification from the dashboard. Your mail sends from your domain, not ours.

Pricing

One price. No plan to choose.

You are charged per message against a prepaid wallet. There is no monthly fee, no minimum, and no contract. If a send fails permanently, you are refunded.

Create a free account

₹0.02per email₹20 per 1,000

SMS (at launch) — India only: ₹0.25 per segment
WhatsApp marketing (at launch): ₹1.00 per message
WhatsApp utility & OTP (at launch): ₹0.35 per message
WhatsApp customer replies (at launch): ₹0.10 per message
Monthly fee: None — pay per message
Aslio Pro (optional): ₹999/mo — 5× rate limit, priority support
AI Agent for WhatsApp (optional): ₹2,499/mo — answers customers for you
Minimum spend: None
Batch sends: Up to 1,000 recipients per call
Delivery webhooks: Included
Refund on permanent failure: Automatic

FAQ

Frequently asked questions

01What is Aslio?+

Aslio is a messaging API by Asli One Global Private Limited: send transactional and marketing email today — with SMS and WhatsApp on the way — from one API and one prepaid wallet. Built in India.

02How much does Aslio cost?+

Email is ₹0.02 per message (₹20 per 1,000), charged against a prepaid wallet. There is no monthly fee, no minimum spend and no contract — and permanently failed sends are refunded automatically.

03Is there a free way to try Aslio?+

Yes. Creating an account is free and your API key is issued as soon as you verify your email. The wallet starts empty, so nothing can be charged until you top it up.

04Does Aslio support SMS and WhatsApp?+

SMS and WhatsApp are in build — SMS with DLT header and template registration handled inside the dashboard, and WhatsApp sending from your own number with your business name. Email is live today.

05Can I send from my own domain?+

Yes. You verify your sending domain with DKIM records shown in the dashboard, so mail is signed as you and lands with your name on it. One-click unsubscribe and delivery webhooks are included.

06Who is Aslio for?+

Developers and businesses in India that want one simple, prepaid messaging API instead of juggling separate email, SMS and WhatsApp providers — from side projects to production applications.

Send your first message today

Create an account, verify your email, and your API key is waiting on the other side. The wallet starts empty, so nothing can be charged until you top it up.

Create a free account Read the docs