Softwr

Surveys · head to head

Fillout vs Wunderkind

Fillout logo

Fillout

Surveys

Form builder that reads and writes records in Airtable, Notion, HubSpot and Salesforce, with unlimited seats on every plan including the free one

From
Free
Free plan
Yes
Full reviewWebsite
Wunderkind logo

Wunderkind

Marketing

Identity resolution and triggered messaging for high-traffic retailers, formerly BounceX

From
On request
Free plan
No
Full reviewWebsite

The short version

  • Only Fillout has a free tier, so it costs nothing to try first.
  • Each has a real cost: Fillout the Business plan is marketed with unlimited responses but the fair use policy names thresholds of 30,000 submissions a month, 250,000 in total, 500 forms per account and 50 GB of uploads a month, above which the vendor may limit or suspend features, so unlimited means unmetered rather than uncapped.; Wunderkind pricing is never published and deals are annual with revenue-share terms and a floor, so the effective cost only becomes clear after a year of attributed revenue you have already paid against.
  • They diverge on capability: Fillout covers Unlimited seats and forms, Wunderkind covers Identity resolution network.
  • Prices and features above were last checked on 31 August 2026.

Where they differ

Only the attributes on which Fillout and Wunderkind actually diverge.

Attributes where Fillout and Wunderkind differ
AttributeFilloutWunderkind
Starting priceFreeOn request
Pricing modelPer month by response countquote
Free tierYesNo
CategorySurveysMarketing

Identical on both: platforms (Web, API), user rating (Not yet rated).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in Fillout

  • Unlimited seats and forms
  • Database read and write
  • Soft response limits
  • Conditional logic and calculations
  • EU hosting
  • REST API and webhooks

Only in Wunderkind

  • Identity resolution network
  • Triggered email
  • Text message marketing
  • Onsite behavioural messaging
  • Performance-linked pricing
  • Managed service model
  • Attribution reporting
  • Email service provider integration

What people use each for

The jobs each tool is most often brought in to do.

Fillout

  • A team already running on Airtable or Notion that wants forms which update existing records rather than appending new rowsnot Wunderkind
  • An organisation with many occasional form builders, where per-seat pricing elsewhere would cost more than the forms are worthnot Wunderkind
  • Replacing a survey tool, a scheduling tool and a payment link with one form that does all threenot Wunderkind
  • Public forms that must keep collecting through an unexpected traffic spike rather than shutting off at a quotanot Wunderkind

Wunderkind

  • A large apparel retailer that captures email addresses from only a small share of its traffic and wants to message the rest of its cart abandonersnot Fillout
  • A publisher converting anonymous readers into newsletter subscribers and paid subscription prospects at volumenot Fillout
  • A travel brand with long consideration cycles that wants triggered messaging on browse behaviour without waiting for a form fillnot Fillout
  • A retailer that already has a capable ESP and wants an additional revenue channel layered on top rather than a platform replacementnot Fillout

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

Fillout

  • The Business plan is marketed with unlimited responses but the fair use policy names thresholds of 30,000 submissions a month, 250,000 in total, 500 forms per account and 50 GB of uploads a month, above which the vendor may limit or suspend features, so unlimited means unmetered rather than uncapped.
  • EU data residency begins on the Team plan at 250 USD per month, more than three times the Business price, and is not applied automatically; you must upgrade and then raise a support request to be moved.
  • The Team plan is hidden behind a secondary tab that does not render without interaction, so buyers reading the pricing page see Business at 75 USD as the top self-serve tier and only discover the 250 USD step when they ask for single sign-on or EU hosting.
  • The enterprise marketing page lists hosting in the United States, EU, United Kingdom, Australia and Canada, but the security documentation and subprocessor list name only the United States and the EU, so three of those five regions should be confirmed in writing before they are relied on.
  • The vendor is SOC 2 Type 2 but claims neither ISO 27001 nor HIPAA anywhere in its documentation, and it is angel-funded with no disclosed institutional round while the parent company now trades as Zite and ships a separate AI application builder.

Wunderkind

  • Pricing is never published and deals are annual with revenue-share terms and a floor, so the effective cost only becomes clear after a year of attributed revenue you have already paid against.
  • You pay against Wunderkinds own attribution of the revenue it claims to have driven, so the lookback window, credit rules and whether a genuine holdout test is run are commercial terms that materially change your bill and are easy to leave vague.
  • The model needs scale: a site without substantial traffic generates too few identity matches to clear a contract floor, which makes it uneconomic for mid-market retailers however good the pitch sounds.
  • Messaging people who never gave you their email address on your own site carries privacy exposure and brand risk, and it sits uncomfortably with several regulatory regimes and with some consumers regardless of legal defensibility.
  • The identity network is densest in the United States, so a European or Asian retailer gets materially lower match rates and a weaker business case, and the model interacts badly with strict consent regimes such as GDPR.

Pricing, plan by plan

Fillout

Free
  • FreeFree
    • 1,000 responses per month
    • Unlimited forms and unlimited seats
    • 20 MB per file upload
  • Starter$15/month
    • 180 USD per year billed annually, a stated 20 percent saving on monthly billing
    • 2,000 responses per month
    • Unlimited forms and seats
  • Pro$40/month
    • 480 USD per year billed annually
    • 5,000 responses per month
    • Branding fully removed at this tier
  • Business$75/month
    • 900 USD per year billed annually
    • Marketed as unlimited responses, subject to a fair use threshold near 30,000 per month
    • 1 GB per file upload

Wunderkind

On request
  • Wunderkind for Email$undefined/year
    • Identity resolution and triggered email programmes
    • Managed strategy and campaign operation
    • Annual contract with performance-linked commercial terms
  • Wunderkind for Text$undefined/year
    • SMS programmes against the identity graph
    • Consent and suppression management
    • Annual contract with performance-linked commercial terms

Which should you pick?

Choose Fillout if

  • You need unlimited seats and forms.
  • You want to start without paying.
  • You work on Web, API.
  • You also want database read and write.
Fillout review

Choose Wunderkind if

  • You need identity resolution network.
  • You work on Web, API.
  • You also want triggered email.
Wunderkind review

Questions people ask

Is Fillout or Wunderkind better?
Neither clearly leads. Fillout starts at Free and Wunderkind at On request, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Fillout or Wunderkind?
Fillout has a free tier; the other does not. Paid plans start at Free for Fillout and On request for Wunderkind.
Does Fillout or Wunderkind run on more platforms?
Both run on Web, API, so platform support will not decide this one for you.
Can I use Fillout for free?
Yes. Fillout has a free tier, so you can try it without paying. Wunderkind starts at On request.
What is Fillout best used for?
Fillout is most often used for a team already running on airtable or notion that wants forms which update existing records rather than appending new rows, an organisation with many occasional form builders, where per-seat pricing elsewhere would cost more than the forms are worth, replacing a survey tool, a scheduling tool and a payment link with one form that does all three, public forms that must keep collecting through an unexpected traffic spike rather than shutting off at a quota. Of those, a team already running on airtable or notion that wants forms which update existing records rather than appending new rows and an organisation with many occasional form builders, where per-seat pricing elsewhere would cost more than the forms are worth are not what Wunderkind is typically brought in for.
What can Fillout do that Wunderkind cannot?
Fillout covers Unlimited seats and forms, Database read and write, Soft response limits, Conditional logic and calculations. Wunderkind covers Identity resolution network, Triggered email, Text message marketing, Onsite behavioural messaging.

Answered from the vendors’ own pages

Fillout: Are seats really unlimited?

Yes. The vendor states there are no per-seat charges on any plan, including Free, and forms are unlimited too. Responses per month is the only meter below the Business tier.

Wunderkind: Is Wunderkind the same as BounceX?

Yes. BounceX rebranded as Wunderkind in 2019; the identity resolution and triggered messaging model is the same lineage.

Fillout: What happens when I exceed my response quota?

Nothing breaks. Forms keep collecting, and you can upgrade, buy bulk submissions or wait for the monthly reset.

Wunderkind: How is Wunderkind priced?

It is not published. Contracts are annual and structured around a share of revenue Wunderkind attributes to its messages, usually with a minimum commitment.

Fillout: Can I host respondent data in the EU?

Only from the Team plan at 250 USD per month, and only after contacting support to switch. Note that email and payment subprocessors remain in the United States regardless.

Wunderkind: Does it replace my email platform?

No. It runs alongside your existing ESP and adds a triggered channel; it is not a campaign management replacement.

Fillout: Is the Business plan really unlimited responses?

It is unmetered, not uncapped. The fair use policy names roughly 30,000 submissions a month as the point at which the vendor may intervene, so treat that as the practical ceiling.

Wunderkind: Will it work outside the United States?

Less well. The identity network is concentrated in the US, and consent requirements in Europe reduce both match rates and the legal room to message unidentified visitors.

Share

Related pages

More on Fillout

More on Wunderkind

Keep looking

Other head to heads