What does Nixflex cost?

A flat $0.08 per minute of voice, everything included - no monthly platform fee, no per-feature meters. Web chat is $0.01/message, browser calls $0.09/min.

Can I test before switching?

Yes - $10 free credit with no card (about 125 minutes), and a live agent on the homepage you can talk to without signing up.

Alternative · 2026

The Synthflow alternative with one flat price

Q: Do I have to port my phone numbers to switch?

No - Nixflex is bring-your-own-carrier. Your numbers stay in your Twilio or Telnyx account and import with one API call.

Nixflex runs AI voice agents at a flat $0.08/min with everything included - on your own carrier numbers, with no monthly fee and no lock-in. Here is the honest case, and the four-step switch.

Why people look for a Synthflow alternative

Synthflow is a friendly no-code builder with EU hosting by default - real strengths. The alternative-searchers are usually feeling one of two things: the per-minute range (their own docs state `$0.15–`$0.24 once everything is counted) or the ceiling of a visual builder once their product needs an API underneath. Nixflex answers both: `$0.08 flat, API-first with a full dashboard on top.

THE 1,000-MINUTE BILL · LIVE

Nixflex — flat, all-in$80

Synthflow`$150–`$240

Sources: Nixflex flat `$0.08/min. Synthflow advertises from `$0.09/min while their own documentation states a real range of `$0.15–`$0.24/min.

What you get on Nixflex

One flat price with the whole stack inside: $0.08 per minute of voice covers speech recognition, the AI, the voice, real calendar booking, the two-way SMS agent, webhooks and post-call analysis. No monthly platform fee, no per-feature meters, no gated tiers. Your own Twilio or Telnyx numbers carry the calls at carrier rates with zero markup - and they stay in your account, so there is no lock-in by design.

Underneath sits an engine that enforces the things prompts can only request: a booking cannot be confirmed unless the calendar truly accepted it, outbound voicemail is recognised by the engine itself on any carrier, and a failing custom-API tool never crashes a live call. Data lives on EU infrastructure (Ireland) with automatic 90-day deletion - a straight answer for GDPR questionnaires.

Switching, honestly: four steps

Free, $10 credit, no card - about 125 minutes of testing.

Import your numbers

Your Twilio or Telnyx numbers, one API call each - no porting, they never leave your carrier account.

Recreate your agent

Paste your prompt, pick a voice, connect your calendar and webhooks - the concepts map one-to-one.

Test side by side

Run real calls on both platforms with the same prompt. Keep whichever wins - your numbers repoint with one webhook change.

Frequently asked

Do I have to port my phone numbers?

No - this is the key difference from most migrations. Nixflex is bring-your-own-carrier: your numbers stay in your Twilio or Telnyx account, you import them with one API call, and switching direction later is a webhook change.

Will my prompts work?

Prompts are plain instructions and transfer directly. The concepts - agents, numbers, tools, webhooks - map one-to-one, so an afternoon is usually enough for a working replica of your current agent.

Is Nixflex EU-hosted like Synthflow?

Yes - EU infrastructure (Ireland) by default, encrypted, automatic 90-day deletion, DPA available. Synthflow deserves credit for the same default; the difference is the price and the API-first platform.

Can I run both platforms during the switch?

Yes, and you should: point one number at Nixflex, keep the rest where they are, and compare real calls for a week. $10 of free credit covers the pilot without a card.

Try the alternative in your browser - right now

A live Nixflex agent is on the homepage. No signup, no meeting, no card.

Talk to a live agent Full Nixflex vs Synthflow comparison