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Tech riderRev. 24 Sept 2026

Alert21

Ch 585.7of 77Transactional SMS Software
  1. 1Runs onWeb
  2. 2Pay-as-you-goYes
  3. 3SMS APIYes
  4. 4Delivery statusYes
  5. 5WebhooksYes
5 lines stated Written from the maker's own pages: alert21.in
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Overview

Alert21 is ranked #58 of 77 in transactional SMS software on Specifiction. It runs on Web.

Alert21 plans and pricing

All plans
SMS pay-as-you-go Usage-based billing · Volume discounts as sending scale grows · Prepaid balance in Indian Rupees alert21.in · 24 Sept 2026

Compared on transactional SMS software

Pay-as-you-go
Yesalert21.in
SMS API
Yesalert21.in
Delivery status
Yesalert21.in
Webhooks
Yesalert21.in

Company

Headquarters
Greater Noida, Uttar Pradesh, Indiaalert21.in · 4 Oct 2026

Best Alert21 alternatives

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All accessCh 01 ClickSend SMS API Free trialAPIiOS 7.3 All accessCh 02 Textmagic Free trialAndroidAPI from $0.05/mo7.3 All accessCh 03 Bandwidth Messaging API Free trialAPIWeb 7.2 All accessCh 04 D7 Networks Free trialAPIWeb 7.1 All accessCh 05 Clickatell SMS API Free planFree trialAPI Free to start7.0 All accessCh 06 Mailchimp Free planWebiOS Free to start7.0

Where it ranks on Specifiction

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Sources