What Actually Happens When Your Supplier Goes Out of Stock
If you're dropshipping on Shopify, your entire business depends on suppliers you don't control. You don't hold inventory. You don't pack boxes. You place an order with your supplier after a customer pays you — and pray the product is still in stock.
When that prayer goes unanswered, the consequences stack up fast:
Lost sales are the obvious hit. A customer lands on your product page, clicks "Add to Cart," and completes checkout. Your Shopify store processes the payment. Then you log into your supplier's site and see "Out of Stock." Now you have a customer who paid for something you can't deliver.
Refunds erode your margins. You refund the customer, but Stripe still keeps its processing fee. On a $50 order, you're out $1.75 just for the privilege of not selling anything. Scale that to 20 failed orders a month and you're losing $35/month in processing fees alone — before counting the actual lost revenue.
Negative reviews compound the damage. A customer who orders something and gets a refund email three days later doesn't just move on. They leave a 1-star review. They file a PayPal dispute. They tell their friends. One bad review on a product with 12 reviews tanks your conversion rate by 15-20%.
Your ad spend burns while you sleep. This is the one most dropshippers miss. Your Facebook or TikTok ads keep sending traffic to a product page for something you can't fulfill. At $30-50/day in ad spend, every day your supplier is out of stock costs you real money with zero chance of ROI. We've seen stores waste $500+ on ads for out-of-stock products before anyone noticed.
REAL EXAMPLE
A pet supplies dropshipper we audited had 4 of their 8 best-selling products at HIGH or CRITICAL stockout risk. Their top-selling cat tree ($239.99) had only 2 of 4 suppliers with inventory — and the primary supplier was down to fewer than 20 units. At their sales velocity, they were 10 days from losing their #1 revenue product. Read the full case study →
3 Ways to Check Supplier Stock Manually (And Why They Don't Scale)
Before we get into automation, let's cover the free, manual approaches. If you have fewer than 10 products and 1-2 suppliers, these can work. Beyond that, they fall apart.
THE DAILY LOGIN CHECK
The simplest approach: log into AliExpress, CJ Dropshipping, or your supplier's website every morning and manually check stock levels for each product you sell.
Why it breaks: At 20 products with 2 suppliers each, you're spending 60-90 minutes every morning just checking stock. Miss one day — like a weekend or holiday — and a stockout slips through. Most dropshippers do this for a week, then stop.
THE SPREADSHEET TRACKER
A step up from the daily login: create a Google Sheet with your product URLs, supplier links, last-known stock levels, and a "checked on" date column. Color-code rows by risk level.
| SKU | SUPPLIER | STOCK | CHECKED | STATUS |
|---|---|---|---|---|
| CAT-TREE-01 | AliExpress #1 | 18 units | Mar 18 | ⬤ LOW |
| CAT-TREE-01 | CJ Drop | 45 units | Mar 17 | ⬤ MED |
| BED-ROUND-02 | AliExpress #3 | 200+ units | Mar 15 | ⬤ OK |
Why it breaks: The spreadsheet is only as good as the person updating it. Stock levels change hourly, but you're checking daily (at best). And there's no alert — you have to remember to look. By the time you notice a problem in your spreadsheet, customers have already ordered a product you can't ship.
THE "ASK YOUR SUPPLIER" METHOD
Some dropshippers build a relationship with their supplier and simply ask them to notify when stock runs low. This works surprisingly well… when it works.
Why it breaks: Your supplier has thousands of buyers. You're not their priority. AliExpress sellers change stock without warning, go on holiday for weeks, or simply discontinue products. Relying on a supplier to proactively notify you is betting your business on someone else's to-do list.
HOW MUCH ARE STOCKOUTS COSTING YOU?
Use our free calculator to get an instant estimate of your annual revenue at risk from supplier stockouts.
CALCULATE MY RISKFREE STOCKOUT RISK AUDIT
We'll manually check your top 10 products against real supplier stock levels and send you a risk report within 24 hours. No payment required.
How to Set Up Basic Stock Monitoring for Free
If you're not ready to pay for a tool, you can cobble together a basic monitoring system using free services. Here's a setup that actually works — we're giving you the real playbook.
→ Step 1: Use Visualping or Distill.io for Page Change Alerts
These free browser extensions monitor any webpage for changes. Set them to watch your supplier's product page and alert you when the stock quantity or availability text changes.
# Visualping Setup (free tier: 65 checks/month) 1. Install the Visualping Chrome extension 2. Navigate to your supplier's product page on AliExpress 3. Select the area around the stock/quantity indicator 4. Set check frequency to every 6 hours (free tier limit) 5. Choose email notification 6. Repeat for each product URL # Distill.io Setup (free tier: 25 monitors) 1. Install Distill.io Chrome extension 2. Open your supplier product page 3. Click Distill icon → "Monitor parts of page" 4. Select the stock count element 5. Set condition: notify when text changes 6. Check interval: 6 hours (free tier)
Limitation: Free tiers give you 25-65 checks per month total. With 10 products checked every 6 hours, you'll burn through that in 2-3 days. You'll need the paid tier ($10-15/month) for meaningful coverage.
→ Step 2: Google Sheets + IMPORTXML for Stock Scraping
Google Sheets has a built-in function called IMPORTXML that can pull data from any public webpage. You can use it to automatically fetch supplier stock numbers into a spreadsheet.
# In Google Sheets, paste this formula:
=IMPORTXML("https://aliexpress.com/item/YOUR_PRODUCT_ID.html",
"//span[@class='product-quantity']")
# Create columns:
# A: Product Name
# B: Supplier URL
# C: =IMPORTXML(B2, "//span[contains(@class,'quantity')]")
# D: =IF(C2<50, "⚠️ LOW STOCK", "✅ OK")
# E: =NOW() (last checked timestamp)
# Set a Google Apps Script trigger to refresh every hour:
function refreshData() {
var sheet = SpreadsheetApp.getActiveSheet();
var range = sheet.getDataRange();
range.setValues(range.getValues()); // forces recalculation
}Limitation: IMPORTXML breaks constantly. AliExpress and most supplier sites use JavaScript-rendered content that IMPORTXML can't read. It also gets rate-limited. Expect this to work for about 40% of supplier pages, and to break without warning when suppliers update their site layout.
→ Step 3: Zapier/Make.com for Alert Routing
Connect your monitoring tools to Slack, SMS, or email using Zapier's free tier. This way, when Visualping or Distill.io detects a change, you get a push notification instead of just an email.
# Zapier free tier setup:
Trigger: "New email from Visualping" (Gmail trigger)
Filter: Subject contains "changed" AND body contains "out of stock"
Action: Send Slack message to #inventory-alerts
# Or use Make.com (formerly Integromat):
Trigger: Watch Gmail for Distill.io alerts
Router: If stock < 50 → send SMS via Twilio
If stock = 0 → pause Shopify product + send Slack alertLimitation: Zapier free tier gives you 100 tasks/month. Make.com gives 1,000 operations. Either way, you're limited in how many alerts you can process before hitting a paywall.
THE HONEST MATH ON "FREE" MONITORING
If you string together Visualping (paid tier at $10/mo) + Google Sheets + Zapier (paid at $20/mo), you're at $30/month for a fragile system that monitors maybe 15 products reliably. When a supplier changes their page layout — and they will — your IMPORTXML formulas break silently and you don't find out until a customer complains.
This DIY setup covers maybe 60% of what you need. It won't tell you about stock trends (is a product selling down fast?), won't check backup suppliers automatically, and won't pause your Shopify listings when stock hits zero.
For stores doing under $5K/month, this might be enough. Beyond that, the cost of a single stockout-driven refund spiral will exceed what you'd pay for proper tooling.
How Stockly Automates All of This
We built Stockly because we watched dropshippers lose thousands of dollars to a problem that shouldn't exist in 2026. Here's what the platform does — and how it replaces the entire DIY stack above.
CONTINUOUS SUPPLIER MONITORING
We check your supplier stock levels every few hours across AliExpress, CJ Dropshipping, Alibaba, and private suppliers. Not with IMPORTXML hacks — with purpose-built scrapers that handle JavaScript rendering, CAPTCHAs, and page layout changes.
MULTI-SUPPLIER INTELLIGENCE
For every product you sell, we identify and track backup suppliers. When your primary supplier drops below your threshold, we've already verified which backups have stock, what their pricing looks like, and how fast they ship.
SMART ALERTS WITH CONTEXT
You don't get a generic 'stock changed' email. You get: 'SKU CAT-TREE-01 is down to 18 units at your primary supplier. At your current sales velocity of 3/day, you have ~6 days before stockout. Backup supplier CJ-4482 has 200+ units at $72/unit.'
TREND ANALYSIS & FORECASTING
We track supplier stock levels over time so you can see depletion curves. If a product is selling down 15% faster than last month, you'll know before it becomes an emergency — not after.
SHOPIFY INTEGRATION
Connect your Shopify store and we'll map your products to supplier SKUs automatically. When a supplier goes to zero, we can flag the product in your dashboard so you can pause ads or swap suppliers before customers notice.
Normally $299/month. As a founding member, your first month is $99 — full access to every feature. Cancel anytime, no questions asked. We're pricing it low because we want your feedback to shape the product.
Manual vs. DIY vs. Stockly
| FEATURE | MANUAL | DIY TOOLS | STOCKLY |
|---|---|---|---|
| Check frequency | 1×/day | Every 6hrs | Every 2-4hrs |
| Products monitored | 10-15 max | 15-25 | Up to 100 |
| Backup supplier tracking | No | No | Yes |
| Depletion forecasting | No | No | Yes |
| Alert quality | You notice it | Generic email | Contextual + actionable |
| Setup time | None | 3-4 hours | 15 minutes |
| Monthly maintenance | 60-90 hrs | 5-10 hrs | 0 hrs |
| Breaks when site changes | N/A | Yes | We fix it |
| Monthly cost | Free (your time) | ~$30 | $99 (founding) |
Start With a Free Stockout Audit
Not sure if stockouts are actually a problem for your store? Let us check. Drop your Shopify URL below and we'll manually audit your top 10 products against real supplier stock levels. You'll get a report showing which products are at risk, which suppliers are running low, and what to do about it.
It's free, takes us about an hour to compile, and you'll have it in your inbox within 24 hours. No credit card, no sales call, no commitment. If your inventory looks healthy, we'll tell you that too.