Comparison
Publish Now Email Validation vs Kickbox
Kickbox gives you 100 free verifications, then bills you for everything after that. Publish Now is free for the 70 to 90% case Kickbox charges for - syntax, MX, dead-domain detection - the bulk of what any first-pass tool actually catches.
Side by side
Pricing from Kickbox's public page. Accuracy figures from the LeadMagic 2026 benchmark and vendor claims.
| Feature | Publish Now | Kickbox |
|---|---|---|
| Price | Free | $0.008/email with volume discounts down to ~$0.004 at scale |
| Free tier | Unlimited (rate-limited) | 100 verifications with signup; paid-only after that |
| Accuracy | 70–90% (MX + DoH) | 95%+ (their claim) / mature, brand-trusted accuracy in line with the paid-validator pack |
| Signup required | ||
| API available | — (roadmap) | |
| SMTP probing | ||
| Catch-all handling | Limited | Yes |
| Best for | Free first-pass list cleanup before send | Established marketing teams that want a brand-trusted vendor with mature integrations. |
Pick Kickbox if…
- ▸Your procurement team prefers a long-established vendor with case studies and a brand they recognize.
- ▸You already use Mailchimp, HubSpot, Marketo, or another platform with a native Kickbox integration.
- ▸You want their Sendex score (a per-address quality rating) baked into your CRM or ESP workflow.
Pick Publish Now if…
- ▸You blew through Kickbox's 100 free verifications and do not want to top up just to clean one CSV.
- ▸You are a solo founder or indie hacker and a paid validator is not in this month's budget.
- ▸You need the basic 70 to 90% catches - bad syntax, dead domains, no MX - and a Sendex score is overkill for your use case.
Frequently asked
Is Publish Now as accurate as Kickbox?
For the first pass, yes. We catch the same 70 to 90% of bad addresses on syntax, MX, and dead-domain checks. Kickbox layers a Sendex quality score and SMTP confirmation on top, which is useful if you are paying for it. For free cleanup, we cover the bulk.
Why is Publish Now free when Kickbox charges after 100 verifications?
Kickbox built a real business on paid SMTP confirmation and Sendex scoring, both of which are infrastructure-heavy. We run a leaner stack - MX plus DoH on Cloudflare Workers - so there is no per-verification cost to recoup.
Should I use Kickbox or Publish Now first?
Run Publish Now first to strip the dead weight at $0. If you still want Kickbox's Sendex quality score on the survivors, push the smaller list through their API. Your Kickbox bill drops, your sending stays clean.
Can I use Publish Now if I am already a Kickbox customer?
Yes, and it is a smart pairing. Free MX cleanup with us, paid SMTP and Sendex with them. The two passes are complementary, not competitive.
Does Publish Now have a Sendex-equivalent quality score?
No. We return a binary verdict on each address (valid, invalid, unknown for catch-alls). If you need a numeric quality score for ESP segmentation, Kickbox is the right tool for that layer.