Bulk API High-volume batch processing
POST JSON batches of domains, IPs, and URLs to https://api.ismalicious.com/bulk/check. One synchronous response with per-entity verdicts, confidence, and categories.
No credit card required · Free API key
Database Scale
What you're checking against when you call the bulk API.
Current data sample
500 000 000
Total threats
200 000 000
Malicious domains
250 000 000
Malicious IPs
594+
Data sources
No credit card required · Instant access to full datasets
10–100
Entities/Request
JSON
In / Out
0 call
Synchronous
Plans
Scaled limits
Key features. Everything you need to protect your infrastructure and users.
Single POST
One request returns all entity results plus processingTimeMs.
JSON body
{ entities: string[], enrichment?: string } — simple integration.
Mixed types
Domains, IPs, and URLs in the same entities array.
Plan limits
GET /bulk/check returns your max batch size and usage.
Structured results
isMalicious, confidence, sources, categories per row.
Same auth
X-API-KEY (Base64 apiKey:apiSecret) like /check.
Use cases. How security teams use this tool.
Log Enrichment
Enrich SIEM logs with threat data in batch.
List Validation
Validate blocklists and IOC lists against our intel.
Email Processing
Check all URLs and domains from email batches.
Threat Hunting
Analyze large sets of IOCs during investigations.
Batch checks in one request
POST https://api.ismalicious.com/bulk/check with { "entities": [...], "enrichment": "full" }. The API responds with success, total, processed, results[] (entity, type, isMalicious, confidence, sources, categories), optional errors[], and processingTimeMs. Authentication uses X-API-KEY with Base64(apiKey:apiSecret).
Plan limits
Maximum entities per request scales with subscription (10 on Free and 100 on Pro). Use GET /bulk/check to retrieve documentation and limit metadata for your key.
When to use bulk vs single check
Use bulk for dashboards, CSV validation, or moderate-sized lists. For deep per-entity reports or streaming progress, use GET /check or SSE /check/stream.
Larger workloads
For lists longer than your plan allows, chunk requests client-side and respect rate limits. See /api-docs/rate-limits and your dashboard usage.
Frequently asked questions.
How many items can I submit per request?
What input formats are supported?
Is processing synchronous?
Can I get full enrichment per entity?
Related tools.
Related articles. Learn more from our security research blog.
Ready to get started?
Join thousands of security teams using isMalicious to protect their infrastructure.
No credit card required · Free API key