A web scraping vendor’s SLA should guarantee four things: data accuracy above 99%, a defined uptime and run success rate, a fast incident response time, and legal and compliance protection. If your vendor’s SLA does not put numbers on all four, you are buying a promise, not a service.
This data note breaks down what “good” looks like for each guarantee, so you know what to ask for before you sign.
Why This Matters Before You Sign
A vague SLA puts all the risk on you, the buyer.
Most web scraping contracts fail the same way. They read well. They mention “high accuracy” and “reliable delivery.” But they never say what those words mean in numbers.
- If accuracy is not a number, the vendor decides what counts as accurate.
- If uptime is not a number, a bad week has no consequence.
- If response time is not a number, you wait as long as the vendor wants you to wait.
At ScrapeHero, we have reviewed and negotiated SLAs across e-commerce pricing, MAP monitoring, real estate, and competitive intelligence programs. The pattern is always the same: the SLAs that protect buyers are specific. The ones that protect vendors are vague.
Before you look at any vendor’s SLA, know the five guarantee categories it needs to cover.
1. Data Accuracy Guarantees
A vendor’s SLA should guarantee a specific, measurable accuracy rate for the fields you care about most.
“High accuracy” is not a guarantee. It is a marketing phrase. A real guarantee names the fields and the number.
Ask your vendor to commit to:
- Field-level accuracy: At least 99% to 99.5% accuracy on critical fields like price, stock status, SKU, and product title.
- Completeness: At least 98% coverage of the URLs, listings, or records you asked for in each run.
- Duplicate rate: No more than 1% to 2% duplicate records per delivery.
- A defined correction process: What happens when the vendor misses the target? Look for a credit, a re-run at no cost, or both.
Watch for this red flag: a vendor that quotes a single “overall accuracy” number without breaking it down by field. A 99% overall score can still mean your most important field, like price, is wrong far more often than that.
We cover this in more depth, with example benchmarks for each metric, in our note on the KPIs to include in a web scraping service SLA.
2. Uptime and Delivery Reliability Guarantees
The SLA should guarantee a run success rate, not just “we’ll try our best.”
Scraping breaks. Websites change their layout. Anti-bot systems update. That is normal. What matters is how fast your vendor catches it and fixes it.
Your SLA should specify:
- Run success rate: 99% or higher for scheduled production jobs. This measures how often a job runs to completion as planned.
- Delivery schedule adherence: A clear cutoff time for when data lands in your system, not “usually within a day.”
- Failover process: What happens if a run fails? Does it retry automatically? Does someone get notified?
A note on “uptime”: in scraping, uptime is not about a server staying online. It is about your data actually arriving, on schedule, in the format you agreed on. Ask vendors to define uptime this way, not as generic infrastructure availability.
3. Incident Response Time Guarantees
The SLA should set a maximum time to detect, respond to, and fix a broken scraper.
Anti-bot updates and site redesigns will break scrapers eventually, no matter who your vendor is. The real test of a vendor is how fast they recover.
Look for tiered response commitments, such as:
- Critical issues (a pipeline stops delivering entirely): fixed within 4 hours.
- Non-critical issues (a minor field is missing or a few records are off): fixed within 24 hours.
- Proactive monitoring: does the vendor detect breakage before you notice missing data, or do you have to report it first?
Ask this direct question during vendor evaluation: “Walk me through what happens, hour by hour, when one of my scrapers breaks at 2 a.m.” A vendor with a real SLA will have a clear, rehearsed answer. A vendor without one will describe a best-effort process.
4. Timeliness and Latency Guarantees
If your use case depends on fresh data, the SLA should guarantee a maximum delay between a source updating and the data reaching you.
Late data can be worse than no data at all. If you are tracking competitor prices for same-day repricing, data that is 12 hours old can lead you to the wrong decision.
Your SLA should state:
- End-to-end latency: for example, 60 minutes or less between a source page update and delivery, for high-frequency use cases like price monitoring.
- Refresh frequency: daily, hourly, or real-time, matched to your actual business need. Do not pay for real-time delivery if daily is enough, and do not accept daily if your use case needs hourly.
5. Legal, Compliance, and Data Governance Guarantees
A strong SLA guarantees how the vendor collects data, not just what data they deliver.
This is the guarantee category buyers skip most often, and it is the one that creates the biggest downstream risk.
Your SLA and underlying contract should cover:
- Scope limits: the vendor commits to collecting only publicly available data, within the scope you defined.
- PII exclusion: a zero-tolerance clause for collecting personally identifiable information, with no exceptions written in.
- Rate limiting: the vendor agrees to respect pre-set request rates so it does not put unnecessary load on target sites.
- Change management: any change to scraping logic or scope gets documented and approved, not made silently.
- Liability and indemnification: who is responsible if the vendor’s collection method creates legal exposure for your business?
These clauses protect your business long after the data itself has been delivered and used. We go deeper into the specific contract language to look for in our guide on 10 web scraping contract requirements that could save your business millions.
A Quick Checklist: What a Good SLA Looks Like
Use this list when you compare vendors or review a contract before signing.
- Accuracy target is a specific number, broken down by field.
- Completeness target is a specific number.
- Duplication rate has a maximum.
- Run success rate or uptime is a specific number.
- Delivery schedule has a defined cutoff time.
- Incident response times are tiered by severity.
- End-to-end latency is defined, if your use case needs fresh data.
- PII exclusion is explicit, with no exceptions.
- Rate limiting and scope boundaries are written down.
- Change management process is documented.
- Remedies are defined: credits, re-runs, or termination rights if targets are missed repeatedly.
If a vendor’s SLA is missing more than one or two of these, keep negotiating. Or keep looking.
What “No Guarantees” Actually Costs You
Skipping this step is not free. It just moves the cost to later.
- Bad pricing decisions. If your MAP monitoring data is 15% incomplete, you are enforcing pricing policy on incomplete information.
- Wasted engineering time. Your team ends up building manual checks to catch what the vendor’s SLA should have caught.
- No recourse. Without measurable terms, you cannot prove the vendor underperformed, so you cannot ask for a credit or an exit.
- Repeated failures. A vendor with no SLA teeth has no real incentive to fix problems fast.
An SLA with numbers turns a vendor relationship into something you can manage. An SLA with only promises turns it into something you have to hope works out.
How ScrapeHero Approaches SLAs
ScrapeHero is a website scraping service built around the guarantees above, not around vague promises. Every managed scraping engagement we run is backed by defined accuracy targets, run success rates, and tiered incident response times, because that is what actually protects a buyer.
If you are evaluating web scraping services in the United States and want to see what a fully specified SLA looks like for your use case, our team can walk you through one built around your data needs.
Get a free quote and see what a real SLA looks like for your business.
Frequently Asked Questions
What is a good accuracy guarantee for a web scraping SLA?
Look for 99% to 99.5% accuracy on your most critical fields, such as price and stock status, not just an overall accuracy score across every field.
What is the difference between uptime and run success rate in web scraping?
Uptime traditionally refers to server availability. Run success rate measures whether your scheduled data collection jobs actually completed and delivered data as planned. For scraping, run success rate matters more.
How fast should a web scraping vendor fix a broken scraper?
Critical failures, where a pipeline stops delivering entirely, should be fixed within 4 hours. Non-critical issues should be fixed within 24 hours.
Does a web scraping SLA need to cover legal compliance?
Yes. A complete SLA states that the vendor collects only publicly available data, excludes personally identifiable information, and respects rate limits on target sites.
