kitio.aiSoundHound AI vs 21X
A side-by-side look at pricing plans, free tiers, features, pros and cons, updated for 2026. SoundHound AI starts at See pricing page and 21X starts at See pricing page. Check both pricing pages for current plans.
At a glance
Best for
Category
Pricing model
Starting price
Free plan
Made by
Based in
Rating
Key features
- Voice-native agents
- Guardrails and rule-based actions
- Human-assisted resolution
- Drive-thru and front desk agents
- Testing and analytics
- Edge and cloud deployment
- AI voice agents
- SMS, RCS and email agents
- Lead qualification
- Appointment scheduling
- Call routing and transfer
- Conversational API
| Feature | SoundHound AI | 21X |
|---|---|---|
| Best for | Voice-native AI agents for service, ordering and commerce | Conversational AI for voice, SMS and email sales and service |
| Category | Customer support | Customer support |
| Pricing model | Paid | Paid |
| Starting price | See pricing page | See pricing page |
| Free plan | No | No |
| Made by | SoundHound AI | Structurely |
| Based in | United States | United States |
| Rating | No ratings yet | No ratings yet |
| Key features |
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Pricing compared
SoundHound AI starts at See pricing page and 21X starts at See pricing page. Check both pricing pages for current plans.
Free plan
Cheapest paid plan
Top plan
Free trial
Prices in USD, checked Oct 29, 2026 or later. Plans change often, so confirm on each tool's site before you buy.
Pros and cons
SoundHound AI
- Built around voice from the start
- Covers many industries and channels
- Human handoff for hard cases
- No public pricing
- Enterprise sales process
- Little for small businesses
21X
- Covers voice, text and email
- API for headless use
- Low per-minute voice rates
- Platform fee not published
- Lowest voice rate needs your own carrier
- Requires guided onboarding
Which one should you choose?
Choose SoundHound AI if you want:
- Built around voice from the start
- Covers many industries and channels
- Human handoff for hard cases
Watch out: no public pricing.
Choose 21X if you want:
- Covers voice, text and email
- API for headless use
- Low per-minute voice rates
Watch out: platform fee not published.
SoundHound AI vs 21X FAQ
What is the difference between SoundHound AI and 21X?
SoundHound AI: Voice-native AI agents for service, ordering and commerce. 21X: Conversational AI for voice, SMS and email sales and service. Both are customer support tools.
Is SoundHound AI or 21X cheaper?
SoundHound AI starts at See pricing page and 21X starts at See pricing page. Check both pricing pages for current plans.
Do SoundHound AI and 21X have free plans?
SoundHound AI: No. 21X: No.
Who makes SoundHound AI?
SoundHound AI is made by SoundHound AI, based in United States.
Who makes 21X?
21X is made by Structurely, based in United States.
Which should I choose, SoundHound AI or 21X?
Choose SoundHound AI if you value built around voice from the start and covers many industries and channels. Choose 21X if you value covers voice, text and email and api for headless use.