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Head-to-head · Phone Verification Software

2Factor.in OTP API vs Voxology Verify API

  • Updated Sep 2026
  • Both researched from official sources
  • 5 checks side by side
Higher score 2Factor.in OTP API #4 in Phone Verification Software 7.2/10 Free plan · paid from ₹4,999/mo Free plan✓ 3 of 4 features Visit 2Factor.in
Voxology Verify API #8 in Phone Verification Software 6.6/10 From $0.02 ✓ 4 of 4 features Visit Voxology

2Factor.in OTP API leads on 1 check, Voxology Verify API on 1, and 3 are even. Who comes out ahead on the 5 yes/no, price and count checks where we have data for both products. The editor score weighs everything else too.

Our verdict

  • Highest score2Factor.in OTP API · 7.2/10
  • Free planonly 2Factor.in OTP API
  • Most featuresVoxology Verify API · 4 of 4

2Factor.in OTP API scores higher on our rubric for phone verification software: 7.2 against 6.6 out of 10; our editors rank them #4 and #8.

2Factor.in OTP API offers free plan; Voxology Verify API doesn't publish it. Voxology Verify API offers otp expiry control; 2Factor.in OTP API doesn't publish it.

2Factor.in OTP API is the better fit for teams wanting SMS and voice OTP with a free plan. Voxology Verify API is the better fit for teams adding SMS or voice verification via API.

  • 2Factor.in OTP API fits best

    Teams wanting SMS and voice OTP with a free plan

  • Voxology Verify API fits best

    Teams adding SMS or voice verification via API

Advertiser disclosure: iTechGuides is reader-supported. We may earn a commission when you click some links. It never changes our verdict. How we rank.

Side by side

Feature 2Factor.in OTP API 7.2/10 Visit ↗ Voxology Verify API 6.6/10 Visit ↗
At a glance
Editor score 7.2 6.6
Ranking #4 in Phone Verification Software #8 in Phone Verification Software
Best for Teams wanting SMS and voice OTP with a free plan Teams adding SMS or voice verification via API
Pricing model Free plan + paid Paid
Starting price Not published Not published
Free plan ✓ (best) Not published
Free trial — —
Deployment Cloud Cloud
Support Email, Live chat, Phone, Tickets, Docs · 24/7 Docs
Built for Solo, Small business, Mid-market, Enterprise Small business, Mid-market, Enterprise
Features 2Factor.in OTP API 3/4 · Voxology Verify API 4/4
SMS verification ✓ ✓
Voice verification ✓ ✓
API access ✓ ✓
OTP expiry control Not published ✓ (best)
Specs
Country coverage 190 countries Not published
Verification methods Sms and voice Sms and voice
Our review
Pros
  • SMS OTP, voice authentication, and automatic fallback routing
  • REST API, SDKs, sandbox testing, webhooks, and delivery receipts
  • Free Starter plan; Growth adds ₹5,000 in messaging credits
  • Send one-time passcodes by SMS or voice call.
  • Set code length and verification time-to-live.
  • Cancel pending verifications and limit code assertions to three attempts.
Cons
  • Starter is limited to sandbox access and free test credits
  • Growth begins at ₹4,999/month, apart from usage-based messaging rates
  • Enterprise features such as dedicated routes and SSO are on the Enterprise plan
  • Channel usage and phone-number charges are additional to the base rate.
  • The listed rates apply to the contiguous United States.
  • Documentation is the listed support channel.
Our verdict

2Factor.in OTP API provides REST APIs and SDKs for phone verification and customer communications. It suits teams that need SMS OTP delivery and verification, with voice OTP available for fallback or voice authentication. The service runs…

Read the review →

Voxology Verify API lets application teams add phone-based checks to sign-ups, logins, or transactions. An application starts a verification, chooses SMS or voice, and can optionally include a brand name in the message or voice script. The…

Read the review →
  1. 2Factor.in OTP APIPhone Verification Software 7.2Free plan · paid from ₹4,999/mo
  2. Voxology Verify APIPhone Verification Software 6.6From $0.02

Strengths and trade-offs

  • 2Factor.in OTP API — where it wins

    • SMS OTP, voice authentication, and automatic fallback routing
    • REST API, SDKs, sandbox testing, webhooks, and delivery receipts
    • Free Starter plan; Growth adds ₹5,000 in messaging credits

    Where it doesn't

    • Starter is limited to sandbox access and free test credits
    • Growth begins at ₹4,999/month, apart from usage-based messaging rates
    • Enterprise features such as dedicated routes and SSO are on the Enterprise plan

  • Voxology Verify API — where it wins

    • Send one-time passcodes by SMS or voice call.
    • Set code length and verification time-to-live.
    • Cancel pending verifications and limit code assertions to three attempts.

    Where it doesn't

    • Channel usage and phone-number charges are additional to the base rate.
    • The listed rates apply to the contiguous United States.
    • Documentation is the listed support channel.
  • 2Factor.in OTP API7.2/10 · Free plan · paid from ₹4,999/mo

    A phone verification API with SMS, voice fallback, and sandbox testing; paid plans start at ₹4,999/month.

    Visit 2Factor.inFull verdict →
  • Voxology Verify API6.6/10 · From $0.02

    A focused verification API with configurable OTPs and a $0.02 base charge per successful verification.

    Visit VoxologyFull verdict →

More comparisons

All phone verification software comparisons → · Full ranking →

Reviewed by iTechGuides Editors · Editorial team · Updated Sep 2026

Last updated · How we research and update