Built for Shopify · Free plan available

Recover the sales you'd lose
to stockouts.

Stocklet lets shoppers join a waitlist on sold-out variants — then emails them a one-click checkout link the moment inventory returns. Not the product page. Checkout.

Coming soon to the Shopify App StoreSee how it works
  • Per-variant waitlists
  • Klaviyo sync included
  • No theme code
  • GDPR-compliant
shop.example.com/products/runner
Velocity Co

Trail Runner — Forest

$148
SML
Sold out — size M

Notify me when available

We'll email you the moment size M is back.

jamie@example.com
Powered by Stocklet Watching variant

1. Sold-out variant

Shopify-nativeTheme app block
ResendTransactional email
KlaviyoBring your own list
Fly.ioGlobally deployed
PostgresMulti-tenant by shop

The stockout tax

Every sold-out variant is a customer the next search result steals.

The shopper who wanted size M in Forest bounces, forgets, and buys from a competitor. You restock four days later — they're gone. Stocklet captures that demand and converts it the moment inventory comes back.

Per-variant waitlists

Size Small waits for Small. Forest waits for Forest. The shopper who asked for the exact variant they wanted is the only one notified when it comes back.

One-click checkout link

Email CTAs drop shoppers into a pre-filled Shopify checkout — variant in the cart, ready to pay. Competitors send them to the PDP and lose them.

Variant-aware widget

The Notify Me block hides on in-stock variants and updates live as shoppers switch options. No popups, no page reloads, no clutter.

Sends within seconds

Driven by Shopify's inventory_levels/update webhook and Resend. No polling, no batching — the moment a variant flips back to in-stock, your waitlist hears about it.

Klaviyo sync included

Pipe new signups straight into your Klaviyo list and trigger your existing flows. Not gated behind a top-tier plan — Klaviyo is in from Starter up.

Recovered revenue, in dollars

Two attribution paths in parallel: hidden cart attribute (exact match) and a 7-day email/variant fallback. So your dashboard shows recovered dollars, not just opens.

How it works

Five steps. None of them yours.

You install once and drop in a block. The rest is a loop Stocklet runs every time a sold-out variant comes back.

  1. 1Merchant

    Install + drop in the block

    One-click install from the Shopify App Store. Drag the Notify Me block onto your product template in the theme editor.

  2. 2Shopper

    Joins a variant waitlist

    On a sold-out variant they type an email and submit. No reload, no account — the form confirms inline.

  3. 3Shopify

    Reports restock via webhook

    inventory_levels/update fires. Stocklet matches the variant to its waitlist within seconds.

  4. 4Stocklet

    Sends a one-click email

    Branded HTML from alerts@stocklet.io. CTA links straight into a pre-filled Shopify checkout for that exact variant.

  5. 5Merchant

    Sees recovered revenue

    Dashboard shows recovered dollars, conversion rate, top product, and a unified activity feed. PII masked.

Recovered revenue, not vanity metrics

Dollars in your dashboard.
Not opens and clicks.

Stocklet measures what your finance team measures: revenue attributed to restock alerts, the conversion rate of those alerts, and the products your customers are most desperate to see come back.

Recovered orders

0

+18% vs last 30d

Recovered revenue

$0

lifetime

Conversion of alerts

0.0%

alerts → purchase

Inventory watched

$0

at list price

Activity Live
  • Order recovered — Trail Runner (M)

    $148.00 · ry***@gmail.com · 2m ago

  • Back-in-stock emails sent · 24 recipients

    Trail Runner — Forest · 5m ago

  • +

    New signup

    ja***@hey.com on Crewneck — Cobalt (L) · 11m ago

  • Order recovered — Crewneck (S)

    $98.00 · ka***@proton.me · 22m ago

  • +

    New signup

    ad***@duck.com on Field Cap (Olive) · 34m ago

Most wanted

  • Trail Runner — Forest (M)42
  • Crewneck — Cobalt (S)31
  • Field Cap — Olive24

Stocklet vs the others

Other apps email shoppers back to a product page. We don't.

Capability
Stocklet
Typical back-in-stock apps
Email CTA destination
Pre-filled Shopify checkout
Product page (lose the click)
Per-variant waitlists
Yes — S ≠ M ≠ L
Often product-wide only
Klaviyo sync
Included from Starter ($9)
Top-tier plan / paid add-on
Revenue attribution
Dollars + cart-attribute match
Opens & clicks
Setup
Drag-in theme app block
Liquid edits, dev help
Focus
Back-in-stock only
Marketing-suite sprawl

Attribution that survives finance review

Two attribution paths.
Run in parallel.

When the order webhook arrives, Stocklet checks both rails. If either ties the purchase back to a signup, it counts as recovered. Each subscription stores signup time, notify time, conversion time, order ID, revenue, and currency.

01High confidence

Cart-attribute (primary)

Every email CTA carries a hidden stocklet_subscription_id cart attribute. The resulting order webhook ties the purchase back to the exact signup with high confidence.

027-day window

Email + variant match (fallback)

If the shopper landed on the site directly within a few days, we match shop + email + variant within a 7-day post-notification window so the credit still lands where it belongs.

Pricing

Start free. Pay when restocks pay you back.

Unlimited shopper signups on every plan. Only the restock emails count toward your cap — and there are no overage fees.

Free

Real product, not a trial. Forever free.

$0forever

50 alerts / month

  • Unlimited shopper signups
  • One-click checkout emails
  • Recovered revenue dashboard
  • GDPR-compliant deletion
Coming soon

Starter

For stores tightening up their PDPs.

$9/month

1,000 alerts / month

  • Everything in Free
  • Custom email branding
  • Full widget customization
  • Klaviyo sync included
Coming soon
Most popular

Growth

For brands with a real restock cadence.

$19/month

5,000 alerts / month

  • Everything in Starter
  • Top products & revenue trends
  • Multi-location support
  • Priority support
Coming soon

Scale

For high-volume catalogs.

$39/month

20,000 alerts / month

  • Everything in Growth
  • Custom sender domain
  • API data export
  • Early access to new features
Coming soon

Unlimited signups on every plan — only restock emails count against your cap. No overage fees. Cancel or change plans anytime.

Built to pass review

Compliance is a feature, not an afterthought.

All three GDPR webhooks

customers/data_request, customers/redact, shop/redact — every required Shopify compliance topic is implemented and exercised.

HMAC-verified end to end

Every webhook and every storefront App Proxy request is signature-checked before any data is trusted.

Encrypted API keys

Klaviyo private keys are encrypted at rest. Plaintext is never returned to the merchant's browser.

PII masked in admin

Customer emails appear as ry***@gmail.com in the dashboard so admin staff don't see raw addresses.

Clean uninstall

On app/uninstalled, session data is removed automatically. shop/redact wipes subscriptions, settings, and sessions in a single transaction.

RFC 8058 unsubscribe

Outgoing emails include List-Unsubscribe and List-Unsubscribe-Post headers — Gmail, Apple Mail, and Outlook render their native one-click unsubscribe.

FAQ

Questions, answered honestly.

The email links straight into a pre-filled Shopify checkout — variant already in the cart. Most competitors drop shoppers back on the product page and lose them to a second decision. Stocklet also reports dollar-level recovered revenue, not just opens and clicks.

Almost certainly. Stocklet ships as a theme app block — drag-and-drop in the theme editor, no Liquid edits. It works with any modern theme (Dawn and the entire current Shopify Theme Store), and listens to the variant-change events from major theme families (Dawn, Archetype, etc.).

No. They enter an email address and submit — no signup, no password. Submissions don't reload the page; success and error messages render inline.

Within seconds. Stocklet listens to Shopify's inventory_levels/update webhook and fires email through Resend with no batch delay. Actual inbox delivery depends on the recipient's provider.

Yes, on Starter and above. Paste a Klaviyo private API key in Settings and optionally pick a list. Every new signup fires a 'Subscribed to Back in Stock' event with the email, product title, image, price, and IDs — your existing Klaviyo flows take it from there.

Two methods run in parallel. The checkout link in every email carries a hidden stocklet_subscription_id cart attribute, so the resulting order webhook ties the purchase back to the exact signup. For orders that didn't come through the email, we fall back to matching shop + email + variant within a 7-day window post-notification.

All three required Shopify compliance webhooks are implemented (customers/data_request, customers/redact, shop/redact). PII is masked in the merchant dashboard. Klaviyo API keys are encrypted at rest and never re-exposed to the browser. App uninstall cleans up session data automatically.

Yes — and it's permanent, not a trial. Free includes 50 alerts/month, unlimited shopper signups, one-click checkout emails, and the recovered revenue dashboard. When you hit your cap, sends pause and the dashboard surfaces missed revenue.

Intentionally narrow. No SMS, no push notifications, no pre-order or coming-soon flows, no price-drop alerts, no email A/B testing, no AI features. One job, done well.

Stop emailing shoppers back to a product page.

Send them to checkout — variant in the cart, ready to pay. Free plan forever. Klaviyo sync from $9. Coming soon to the Shopify App Store.

Coming soon to the Shopify App StoreGet launch updates