For marketplace sellers, it is critically important to know when competitors run out of stock, new items appear, or the assortment changes. Manually checking 50-100 product listings daily takes hours of work. In this article, we will discuss how to automate monitoring product availability on Wildberries, Ozon, Yandex.Market, and avoid getting blocked by anti-scraping systems.
Why Track Competitors' Product Availability
Monitoring product availability on marketplaces gives sellers specific competitive advantages that directly affect profits:
Real Case: A sports nutrition seller monitored the availability of a popular protein among the top 3 competitors. When all three simultaneously ran out of stock (due to a delay from the manufacturer), he raised the price of his product by 15% and earned an additional 340,000 rubles in revenue within a week while competitors awaited a new shipment.
Main Reasons to Monitor Availability:
- Seize Opportunity Windows — when competitors run out of stock, you can temporarily raise prices or increase your advertising budget to capture their traffic.
- Plan Purchases — if everyone in the niche runs out of stock simultaneously, it indicates high demand and it's time to order a new batch.
- Track New Products — be the first to learn about new competitor products and respond quickly.
- Analyze Strategies — understand how competitors manage their stock: do they work on demand, do they maintain a large warehouse?
- Find Dropshippers — if a seller consistently shows "1-2 items in stock," they are likely a dropshipper without their own warehouse.
It is especially critical to monitor availability in highly competitive niches: electronics, children's products, clothing, sports nutrition. There, a difference of 2-3 hours in response to a change in the situation can cost tens of thousands of rubles in lost revenue.
How Marketplaces Protect Against Scraping
Wildberries, Ozon, and Yandex.Market actively combat automated data collection because mass scraping creates server load and can be used by competitors. Here are the main protection methods you will encounter:
⚠️ Important: Wildberries has been particularly aggressive in blocking scraping since the end of 2023. If you attempt to open 50+ product listings in an hour from one IP — you will receive a temporary ban for 24 hours. Ozon is more lenient but also monitors suspicious activity.
Main Protection Methods of Marketplaces:
| Protection Method | How It Works | How to Bypass |
|---|---|---|
| IP Request Limit | IP blocking when exceeding 30-50 requests per hour | Rotate proxies every 10-15 requests |
| User-Agent Check | Blocking bots based on browser headers | Use real User-Agents of modern browsers |
| Cloudflare/DataDome | JavaScript checks and CAPTCHA | Use browser automation (Puppeteer/Playwright) |
| Browser Fingerprinting | Canvas, WebGL, font analysis | Change fingerprints or use ready-made services |
| Behavioral Analysis | Tracking scrolling speed, mouse movements | Add random delays of 2-5 seconds between requests |
Why Regular Proxies Won't Help: If you simply buy cheap data center proxies and scrape through them — you will get blocked. Marketplaces see that requests are coming from hosting provider IPs (Amazon AWS, Hetzner, DigitalOcean), not from real users. For stable scraping, you need residential proxies with IPs from real internet providers.
Ready-made Monitoring Services: Comparison
There are two paths: use a ready-made monitoring service or set up your own solution. For most sellers, ready-made services are the optimal option because they have already solved the proxy and protection bypass issues.
Popular Marketplace Monitoring Services:
| Service | Marketplaces | What It Tracks | For Whom |
|---|---|---|---|
| MPSTATS | Wildberries, Ozon | Availability, prices, sales, positions | Professional sellers, niche analytics |
| SellerFox | Wildberries | Stock by sizes, sales dynamics | Clothing and footwear sellers |
| Moneyplace | Wildberries, Ozon, Yandex.Market | Availability, prices, ratings, reviews | Sellers with a large assortment |
| Keepa (for Amazon) | Amazon | Price history, availability, seller ratings | Working with international marketplaces |
| Custom Parser | Any | Everything you need | Specific tasks, savings on large volumes |
💡 Tip: If you are monitoring fewer than 100 products — use a ready-made service (MPSTATS or Moneyplace). If you need to track 500+ items or have specific requirements (e.g., monitoring regional availability) — it is more cost-effective to set up your own parser with proxies.
Which Proxies to Use for Scraping Marketplaces
The choice of proxy type critically affects the stability of scraping and the number of blocks. Let's discuss which proxies are suitable for each scenario.
Comparison of Proxy Types for Marketplaces:
| Proxy Type | Blocking Speed | Speed | When to Use |
|---|---|---|---|
| Data Center Proxies | High (blocked quickly) | Very fast | Only for testing, not for permanent monitoring |
| Residential Proxies | Low (stable) | Medium | Main option for scraping WB, Ozon, Yandex.Market |
| Mobile Proxies | Very low | Slow | For highly protected sites or when maximum anonymity is needed |
Why Residential Proxies Are the Optimal Choice: Marketplaces see requests from the IPs of regular home users (Rostelecom, MTS, Beeline). Such requests look natural and are rarely blocked. Residential proxies provide a balance between speed and stability — you can scrape hundreds of products a day without blocks.
Proxy Settings for Stable Scraping:
- IP Rotation: change IP every 10-15 requests or every 5 minutes
- Geography: use proxies from the same region as the target audience (for Russia — Russian proxies)
- Protocol: HTTP/HTTPS is suitable for most tasks, SOCKS5 — if API work is needed
- Delays: add random pauses of 2-5 seconds between requests to mimic human behavior
- Proxy Pool: keep at least 20-30 different IPs in rotation for scraping 100+ products a day
Common Mistake: Many sellers buy 1-2 proxies and use them to scrape all products. After a few days, these IPs end up on the marketplace's blacklist. The correct approach is to use a pool of 20-50 proxies with automatic rotation.
Setting Up Availability Monitoring on Wildberries
Wildberries is the most protected Russian marketplace against scraping. Since the end of 2023, they have implemented multi-level protection: browser fingerprint checks, behavior analysis, and strict limits on the number of requests. However, there are proven ways to bypass these restrictions.
Step-by-Step Setup for Monitoring via a Ready-Made Service (MPSTATS):
Step 1: Registration and Plan Selection
- Register on the MPSTATS website (there is a free 7-day trial period)
- Select a plan based on the number of products to be monitored: "Start" (up to 100 products), "Business" (up to 500), "Pro" (up to 2000)
- Even the basic plan is suitable for monitoring availability — this feature is available on all plans
Step 2: Adding Products for Tracking
- Go to the "My Products" section → "Add Products"
- Paste the product SKUs of competitors (can be copied from the address bar of the product listing on WB)
- Or add an entire category through search — the system will automatically pull the top 100 products
- Enable the option "Track Availability by Sizes" (critical for clothing and footwear)
Step 3: Setting Up Notifications
- Go to "Settings" → "Notifications"
- Enable notifications in Telegram (the most convenient way to receive alerts)
- Set up triggers: "Product Out of Stock", "Product Available", "Stock Less Than 10 Items"
- Set the check frequency: every 30 minutes (for hot products) or once every 3 hours (for others)
What You Will Get: As soon as a tracked competitor runs out of stock, you will receive a notification in Telegram. This gives you a 2-6 hour head start to adjust your strategy: raise prices, increase ad bids, or urgently order additional stock if you see high demand.
⚠️ Clothing Hack: On Wildberries, it is critical to track availability for each size separately. Often a competitor's product is "out of stock," but in reality, only unpopular sizes remain (e.g., 3XL). Set up monitoring for popular sizes (M, L, XL) separately — this will provide a more accurate picture.
Tracking Stock on Ozon via API
Ozon provides an official API for sellers, but it only shows information about your own products. To monitor competitors, you will have to use either ready-made services or scraping through proxies.
Two Approaches to Monitoring Ozon:
Approach 1: Ready-Made Service (Moneyplace or MPSTATS)
Advantages: no need to set up proxies, works out of the box, has ready-made dashboards with analytics.
Disadvantages: paid subscription (from 2000 rubles/month), limit on the number of tracked products.
Approach 2: Custom Parser via Proxies
Advantages: full control, can track an unlimited number of products, savings on large volumes.
Disadvantages: requires technical skills or a programmer, costs for proxies.
💡 Ozon Feature: Unlike Wildberries, Ozon shows the exact number of items in stock (up to 10 items), not just "available/not available." This provides more detailed information for analyzing competitors' strategies. If a seller consistently shows "2-3 items," they are likely a dropshipper or are intentionally creating an artificial shortage.
How Ozon Protects Against Scraping:
- Rate Limiting: Limit of 60 requests per minute from one IP (more lenient than WB)
- CAPTCHA: Appears with suspicious activity, but less frequently than on other platforms
- Regional Restrictions: Some products are only available in certain regions — proxies from different cities are needed
For stable scraping of Ozon, residential proxies with rotation every 20-30 requests are sufficient. This will allow monitoring 200-300 products per hour without blocks.
Monitoring Yandex.Market: Features
Yandex.Market is an aggregator of offers from different sellers, so monitoring availability here has its specifics. The same product can be sold by 10-20 different stores, and you need to track who runs out of what.
What Is Important to Track on Yandex.Market:
- Number of Offers — if a product had 15 sellers and now has 8, it means many have removed it from sale (possibly due to unprofitable pricing or supply issues)
- Availability in Yandex's Warehouse — products from the "Market FBS" program (Yandex's warehouse) sell better, and should be tracked separately
- Regional Availability — a product may be available in Moscow but absent in other regions
- Delivery Time — if a competitor offers delivery "tomorrow," while others say "in a week," they gain an advantage
Example of Use:
An electronics seller tracks a popular model of headphones on Yandex.Market. He sees that out of 12 sellers, 8 have run out of stock, and the remaining 4 have raised their prices by 20%. This signals that the supplier is having issues with the batch. The seller urgently contacts his supplier, negotiates a purchase at the old price, and receives the product in 3 days while competitors are still waiting. Result: 47 units sold with increased margin in a week.
Yandex.Market's Protection Against Scraping: Yandex uses an advanced protection system based on its own machine learning technologies. They analyze not only the frequency of requests but also behavior patterns: how quickly you navigate between pages, whether you use filters, and whether you scroll down. A simple parser with delays won't help here — full browser automation is needed.
Automation: How to Get Notifications About Changes
Monitoring product availability only makes sense if you receive real-time notifications. Manually checking the dashboard every 2 hours is inefficient. Let's discuss how to set up automatic alerts.
Notification Channels (from best to worst):
| Channel | Delivery Speed | Convenience | When to Use |
|---|---|---|---|
| Telegram Bot | Instantly | Very convenient | Main channel for urgent notifications |
| 5-15 minutes | Average | For daily reports, not for urgent alerts | |
| SMS | Instantly | Expensive | Only for critical events (TOP-5 products) |
| Webhook | Instantly | Requires integration | For automation: price changes, ad launches |
Setting Up a Telegram Bot for Notifications (using MPSTATS as an example):
- In your MPSTATS personal account, go to "Settings" → "Integrations"
- Find the "Telegram" section and click "Connect"
- A window with instructions will open — you need to send the command /start to the bot @mpstats_bot
- The bot will send you an activation code — enter it in your personal account
- Set up notification types: check "Product Out of Stock," "Product Available," "Price Change"
- Set a minimum threshold for notifications: for example, receive an alert only if stock is less than 5 items
Smart Triggers — Avoid Spam: If you set notifications for every change in availability, you will receive dozens of messages a day. The correct approach:
- For the TOP-10 competitors: notification for any change
- For others: notification only for complete stockouts or reappearance after being out of stock
- Group notifications: receive a summary every 3 hours instead of each change separately
- Quiet Hours: disable notifications at night (from 11 PM to 8 AM) if it’s not a critical product
⚠️ Important: Do not confuse "product out of stock" with "product removed from sale." If a competitor's product has disappeared from the catalog entirely — they may have received complaints or violated marketplace rules. This is a different situation, and you need to react differently (check if they are copying your content).
Common Mistakes in Monitoring and How to Avoid Them
Over the years of working with sellers, we have seen the same mistakes that lead either to blocks or incorrect conclusions from data. Let's discuss the most common ones.
Mistake 1: Using One IP for Scraping
Many buy one proxy server and scrape all products through it. After 2-3 days, this IP ends up on the blacklist, and scraping stops working. The correct approach is to use a pool of at least 20-30 proxies with automatic rotation. For monitoring 100 products a day, 20 IPs are sufficient; for 500 products — 50 IPs.
Mistake 2: Ignoring Regional Differences
On Wildberries and Ozon, product availability depends on the region. A product may be available in Moscow but absent in Yekaterinburg. If your target audience is in the regions, use proxies from those regions for monitoring. Otherwise, you will see an incorrect picture.
💡 Solution: If you operate across Russia, set up monitoring with proxies from 5-7 key regions: Moscow, St. Petersburg, Yekaterinburg, Novosibirsk, Krasnodar, Kazan, Vladivostok. This will provide a complete picture of regional availability.
Mistake 3: Checking Too Frequently
Some sellers set checks every 5 minutes, thinking this will give them an advantage. In practice, this leads to blocks and unnecessary expenses on proxies. For most products, checking once every 1-3 hours is sufficient. The exception is hot products in season (e.g., holiday gifts in December) — in those cases, it makes sense to check every 30 minutes.
Mistake 4: Not Considering the Data Update Time on the Marketplace
Wildberries does not update stock in the catalog instantly but with a delay of 15-30 minutes. If you see that a product is "out of stock," it may have actually run out half an hour ago. Consider this delay when making decisions — there is no need to panic and raise prices immediately.
Mistake 5: Monitoring Only Direct Competitors
Many sellers track only 5-10 direct competitors with similar products. However, it is often more important to look at the entire niche as a whole. For example, if you sell protein, monitor not only specific brands but also the top 50 products in the "Sports Nutrition" category. This will show overall trends: when demand season starts, which flavors are popular, when suppliers have batch issues.
Conclusion
Automating the monitoring of product availability on marketplaces is not just a convenience but a competitive advantage that directly affects profits. You receive information about changes 2-6 hours earlier than competitors who check everything manually, allowing you to quickly adjust prices, advertising budgets, and purchasing plans.
Key takeaways from the article: use ready-made services for monitoring up to 100 products (it's faster and easier), set up your own parser via proxies for larger volumes (500+ products), always use residential proxies with rotation for stable operation without blocks, set up smart notifications in Telegram to avoid spam, and consider regional differences in product availability.
If you plan to set up your own parser for monitoring marketplaces, we recommend using residential proxies — they provide stable access to Wildberries, Ozon, and Yandex.Market without blocks. For highly protected platforms or when maximum anonymity is needed, mobile proxies with cellular operator IPs will suffice.