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Alternatives · Notifications

Knock alternatives (2026)

Knock: Hosted notification workflows. Free to 10k msgs; Starter $250. Not self-hostable.

Its Catch: Closed-source SaaS — not Novu MIT self-host.

Below: 8 free or free-tier tools from the same category (notification tools), free and open source first, then the closest match by shared tags. Each keeps its own Catch.

  1. 1.ntfyHTTP pub-sub notifications you can curl from cron

    Free / OSS · Apache-2.0 · 34.9k GitHub stars

    VerdictThe notification CLI that is actually free. curl it from a cron job.

    CatchAnonymous topics are passwords — guessable names leak other people's alerts. Public ntfy.sh rate-limits; reserved topics need Pro. Dual license means you pick Apache-2.0 or GPLv2, not Apache-only.

  2. 2.ListmonkAGPL-3.0 self-hosted newsletters and transactional mail

    Free / OSS · AGPL-3.0 · 23.8k GitHub stars

    VerdictThe self-host newsletter stack. AGPL, fully free, you run the mail.

    CatchAGPL-3.0 is copyleft — network use means you share modifications. You operate Postgres, SMTP, and bounces. There is no official hosted Listmonk Cloud.

  3. 3.AppriseBSD-2-Clause CLI that talks to a hundred notifiers

    Free / OSS · BSD-2-Clause · 17.6k GitHub stars

    VerdictThe notification Swiss Army CLI. BSD, no meter, no product SKU.

    CatchNot a hosted inbox. There is no pricing page — that is the path. You bring every backend (SMTP, Slack tokens, Twilio). This is a notifier, not ntfy and not Novu.

  4. 4.GotifyMIT self-host push server; Android-first, no ntfy.sh twin

    Free / OSS · OSS/MIT · 16.1k GitHub stars

    VerdictMIT push you self-host. No ntfy.sh-shaped public instance; Android is the client.

    CatchNo public hosted twin like ntfy.sh. Android-first client, not a public pub-sub host. Distinct from ntfy (public ntfy.sh + dual license) and Apprise (CLI fan-out, no inbox).

  5. 5.MauticGPL-3.0 self-host marketing automation; hosted trial is not free

    Free / OSS · GPL-3.0 · 10.8k GitHub stars

    VerdictGPL-3.0 marketing automation. Self-host free; hosted trial is not forever-$0.

    CatchMarketing automation — not Listmonk newsletter/tx alone. Hosted 14-day trial is NOT the free path; self-host is. Distinct from Listmonk.

  6. 6.EdgepushAGPL server + MIT SDK: BYO APNs/FCM on Cloudflare Workers

    Free / OSS · Freemium · 9 GitHub stars

    VerdictAGPL Workers push. Self-host $0; Hosted Free is capped — ignore Pro.

    CatchBYO APNs+FCM on Cloudflare Workers — not ntfy/Gotify self-host pub/sub, not Novu workflow orchestration. Server is AGPL; pitch self-host or Hosted Free caps. Distinct from ntfy, Gotify, and Novu.

  7. 7.ShoveMIT end-to-end Go device-push relay

    Free / OSS · AGPL-3.0 · 283 GitHub stars

    VerdictMIT Go push relay. Self-host free; not Edgepush AGPL Workers.

    CatchEdgepush server is AGPL; Shove is MIT end-to-end Go. Device-push relay — not ntfy/Gotify general pub/sub, not Novu multi-channel workflows. Distinct from Edgepush, ntfy, Gotify, and Novu.

  8. 8.TextbeeMIT Android SMS gateway; Hosted Free 1 device/50 msgs/day

    Free / OSS · Freemium · 3.2k GitHub stars

    VerdictMIT Android SMS gateway. Hosted Free is capped; keep the phone online.

    CatchAndroid phone must stay online; not iOS. SMS hole vs Twilio trials — you own the handset and carrier, not a cloud number product. Distinct from Twilio-class CPaaS.

FAQ

What are the best free alternatives to Knock?
ntfy, Listmonk, Apprise, Gotify, Mautic. All are reviewed on Stack Gems in the same category (notification tools); 8 free or open source.
What is the catch with Knock?
Closed-source SaaS — not Novu MIT self-host.
Is there an open-source alternative to Knock?
Yes: ntfy (Apache-2.0), Listmonk (AGPL-3.0), Apprise (BSD-2-Clause), Gotify (OSS/MIT).

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