CIPA Web Filtering for Libraries

The Library Filtering Balancing Act

Libraries must balance open access and intellectual freedom with their responsibility to protect patrons -- especially children -- from harmful online content. Our platform is purpose-built for library environments, delivering CIPA-compliant filtering with the nuanced controls librarians need. Libraries receiving LSTA or E-Rate funding require CIPA compliant content filtering for schools and libraries to keep that funding secure.

CIPA & E-Rate Compliance

Meet every Children's Internet Protection Act requirement and maintain E-Rate eligibility with documented, auditable filtering policies.

Public Access Safety

Protect minors on public terminals while allowing adults to request overrides for legitimate research -- no over-blocking of educational resources.

Community Protection

Device-level policies let children's areas, teen sections, adult terminals, and staff workstations each have appropriate filtering profiles.

100M+

Domains Classified

Content Categories

<10ms

Lookup Latency

24/7

Database Updates

CIPA Compliance & E-Rate Eligibility

Meet every CIPA requirement while preserving the open access mission libraries are built on

Minor Protection

CIPA requires filtering for minors that blocks access to visual depictions that are obscene or harmful to minors. Our content categories precisely target these requirements, blocking adult content, violence, and other material deemed harmful while allowing educational and research resources to flow freely.

Adult Override Capability

CIPA permits adults to request that filtering be disabled for legitimate research or other lawful purposes. Our platform supports one-click override requests that librarians can approve instantly. Override sessions can be time-limited and logged for compliance documentation without exposing patron browsing details.

E-Rate Funding Protection

E-Rate provides discounts of 20% to 90% on internet access and networking equipment. Compliance with CIPA's technology protection measure requirement is mandatory for participation. Our filtering solution provides the documented compliance evidence needed during E-Rate audits and annual certification reviews.

Internet Safety Policy Support

CIPA requires adoption of an internet safety policy addressing access by minors to inappropriate matter, the safety of minors when using email and social media, unauthorized access, and disclosure of personal information. Our reporting and policy tools generate the documentation needed to demonstrate your internet safety policy is in effect.

Intellectual Freedom and Filtering

The American Library Association's position on internet filtering acknowledges the tension between patron safety and intellectual freedom. Overly aggressive filtering blocks legitimate research, educational content, and health information -- particularly impacting LGBTQ+ resources, reproductive health information, and materials about marginalized communities.

Our classification engine is designed with this concern in mind. We maintain extremely precise category boundaries so that filtering adult content does not inadvertently block sexual health education, LGBTQ+ community resources, or art history content. Our false positive rate is among the lowest in the industry, and we actively test against commonly over-blocked categories to ensure legitimate content remains accessible.

Libraries can fine-tune every category and even set per-URL exceptions. If a specific educational resource is incorrectly blocked, a librarian can whitelist it instantly without waiting for a reclassification cycle. This gives libraries the granular control needed to fulfill their dual obligation to protect and provide access.

Library-Specific Filtering Profiles

Pre-configured profiles designed for the distinct needs of different library user groups

Children's Section

Age-appropriate restrictions

Teen / Young Adult

Moderate filtering

Adult Patron

CIPA minimum + override

Staff Workstations

Administrative access

Public WiFi

BYOD patron devices

Catalog Terminals

Locked to library resources

Print Stations

Restricted to print services

Meeting Rooms

Configurable per booking

Laptop Lending

Checkout device policies

Children's Tablets

Locked-down kid mode

Makerspace / Lab

Creative tool access

Branch Libraries

Per-location customization

Policy Per Terminal, Not Just Per Network

Libraries need different policies on different computers in the same building. The children's area computers require strict filtering, while the adult research terminals across the room need minimal restrictions with override capability. Our platform supports device-level policy assignment, meaning each terminal can have its own filtering profile.

For libraries offering public WiFi alongside wired patron computers, separate policies can apply to each network segment. Patrons connecting personal devices over WiFi get a balanced policy that satisfies CIPA while minimizing inconvenience, while library-owned terminals apply the profile appropriate to their designated area and user group.

Multi-branch library systems manage all locations from a single dashboard. Each branch can have its own policy variations (perhaps the downtown branch needs different rules than the suburban branch), while system-wide baseline rules ensure consistent CIPA compliance across all locations. Branch managers can request exceptions while central IT maintains oversight.

Library Use Cases

How public and academic libraries implement web filtering that respects both safety and access

Urban Public Library System

A metropolitan library system with 25 branches and over 500 public computers deploys our filtering to maintain CIPA compliance across all locations. Children's areas block adult content, gambling, and social media. Adult terminals allow most content with easy override requests. Homeless patrons who rely on library internet for job searches, social services, and communication benefit from policies that do not over-block essential resources. E-Rate audits pass consistently with automated compliance documentation.

Rural County Library

A small rural library serves as the community's primary internet access point. With only 10 public computers and limited IT staff, they need a filtering solution that works without technical expertise. Our pre-built CIPA template deploys in minutes via DNS configuration on their router. The library director manages exceptions from a simple web dashboard. The library maintains its E-Rate discount, which covers 80% of their broadband costs, making the filtering investment essential to continued operations.

University Academic Library

A university library applies minimal content filtering to respect academic freedom while blocking web-based risks. unsafe and restricted content domains are blocked on all networks. Research databases, academic journals, and international resources remain fully accessible. The library's public guest WiFi has slightly more restrictive policies than authenticated university networks. The security-focused approach blocks over 10,000 malicious domain requests monthly without impacting research access.

Children's Library Programming

A library running summer reading programs and after-school homework help uses tablets that children access independently. These devices run a strict filtering profile that whitelists educational sites and blocks everything else. During supervised coding workshops, the librarian temporarily expands access to programming resources. Time-limited policy overrides ensure the strict defaults resume automatically when the session ends, requiring no manual intervention from staff.

$4.6B

Annual E-Rate Funding at Stake

99.5%

Category Accuracy

100M

Domains Classified

Content Categories

Patron Privacy by Design

Libraries have a long tradition of protecting patron privacy. Library records are protected by law in all 50 states, and the ALA's Code of Ethics commits librarians to protecting patron confidentiality. Web filtering must respect this tradition, providing safety without becoming a surveillance tool.

Our platform is designed with patron privacy as a core principle. We do not log individual browsing histories. Filtering decisions happen in real time and are not stored in a way that can be traced back to individual patrons. Aggregate statistics show what categories are being blocked and how often, without identifying who triggered the block.

When adults request filter overrides, the override can be granted anonymously. The system records that an override was provided (for compliance documentation) without logging which patron requested it or what content they accessed. This approach satisfies CIPA documentation requirements while honoring patron privacy rights.

For libraries under pressure from local officials or community groups to monitor patron browsing, our platform's architecture makes it technically impossible to generate individual patron browsing reports. This protects librarians from being placed in ethically compromising positions.

Library Web Filtering FAQ

Common questions from librarians and library IT staff about CIPA-compliant web filtering

Does your filtering satisfy CIPA requirements for E-Rate?

Yes. Our filtering meets all CIPA technology protection measure requirements by blocking access to visual depictions that are obscene, contain child pornography, or are harmful to minors on computers accessed by minors. We provide the documented compliance evidence needed for E-Rate Form 486 certification and respond to USAC audits with comprehensive filtering reports. Many libraries using our platform have successfully maintained their E-Rate eligibility for years.

How do adult patrons request filter overrides?

When an adult patron encounters a blocked page, the block screen includes an override request button. Depending on your library's configuration, this can either: (1) allow immediate self-service override after age verification, (2) send a notification to the reference desk for approval, or (3) provide a timed access code. Override sessions automatically expire after the configured duration. No patron identification is stored in the override log.

Will the filter block legitimate educational or health resources?

Our classification engine is specifically calibrated to minimize over-blocking. We maintain explicit exemptions for established educational institutions, health information providers, LGBTQ+ community resources, reproductive health organizations, and digital literacy resources. Our false positive rate on educational content is below 0.1%. Any incorrectly blocked site can be whitelisted instantly by library staff.

Can we have different policies for children's and adult computers?

Absolutely. Our platform supports unlimited device-level policies. You can assign different filtering profiles to children's area computers, teen terminals, adult workstations, staff machines, catalog-only kiosks, and public WiFi. Each profile has its own category blocks, time restrictions, and override settings. Policies are assigned by IP address, device, or VLAN, requiring no patron authentication.

Do you log individual patron browsing activity?

No. Our platform is designed to protect patron privacy. We provide aggregate statistics (total blocks by category, daily trends, etc.) for compliance reporting, but we do not store individual browsing sessions or link filtering events to identifiable patrons. This privacy-by-design approach aligns with ALA intellectual freedom principles and state library record confidentiality laws.

What about filtering on the library's public WiFi?

Public WiFi can be filtered separately from wired patron computers. Many libraries apply a moderate CIPA-compliant policy to the WiFi network, blocking only the categories required by law, since the library cannot control who connects or manage age-based policies on personal devices. DNS-based filtering applies transparently to all WiFi users without requiring any software installation on patron devices.

Related Resources

More information for library web filtering and CIPA compliance

API Integration for Library Systems

Integrate domain classification directly into your library management software, catalog systems, or custom patron access portals

import requests

# Library patron URL filtering
# Check domains against CIPA compliance categories
API_URL = "https://webfilteringdatabase.com/api/moderate.php"
API_KEY = "YOUR_API_KEY"

# Domains requested by library patrons
patron_requests = [
    "archive.org",
    "gutenberg.org",
    "reddit.com",
    "adult-site.xxx"
]

for domain in patron_requests:
    response = requests.post(API_URL, json={
        "api_key": API_KEY,
        "query": domain
    })
    result = response.json()
    category = result.get("category", "unknown")

    # Apply library CIPA filtering policy
    if category in ["adult", "pornography", "gambling"]:
        print(f"BLOCKED: {domain} ({category})")
    else:
        print(f"ALLOWED: {domain} ({category})")

// Library patron URL filtering
// Check domains against CIPA compliance categories
const API_URL = "https://webfilteringdatabase.com/api/moderate.php";
const API_KEY = "YOUR_API_KEY";

// Domains requested by library patrons
const patronRequests = [
    "archive.org",
    "gutenberg.org",
    "reddit.com",
    "adult-site.xxx"
];

async function checkPatronRequest(domain) {
    const response = await fetch(API_URL, {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({
            api_key: API_KEY,
            query: domain
        })
    });
    return await response.json();
}

// Check each patron request against CIPA policy
for (const domain of patronRequests) {
    const result = await checkPatronRequest(domain);
    const blocked = ["adult", "pornography", "gambling"];
    if (blocked.includes(result.category)) {
        console.log(`BLOCKED: ${domain} (${result.category})`);
    } else {
        console.log(`ALLOWED: ${domain} (${result.category})`);
    }
}

# Library patron URL filtering
# Check a domain against CIPA compliance categories

curl -X POST https://webfilteringdatabase.com/api/moderate.php \
  -H "Content-Type: application/json" \
  -d '{
    "api_key": "YOUR_API_KEY",
    "query": "archive.org"
  }'

# Check multiple library patron requests
for domain in archive.org gutenberg.org reddit.com adult-site.xxx; do
  echo "Checking: $domain"
  curl -s -X POST https://webfilteringdatabase.com/api/moderate.php \
    -H "Content-Type: application/json" \
    -d "{\"api_key\": \"YOUR_API_KEY\", \"query\": \"$domain\"}"
  echo ""
done

<?php
// Library patron URL filtering
// Check domains against CIPA compliance categories
$api_url = "https://webfilteringdatabase.com/api/moderate.php";
$api_key = "YOUR_API_KEY";

// Domains requested by library patrons
$patron_requests = [
    "archive.org",
    "gutenberg.org",
    "reddit.com",
    "adult-site.xxx"
];

foreach ($patron_requests as $domain) {
    $ch = curl_init($api_url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_POST, true);
    curl_setopt($ch, CURLOPT_HTTPHEADER, [
        "Content-Type: application/json"
    ]);
    curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode([
        "api_key" => $api_key,
        "query"   => $domain
    ]));

    $response = curl_exec($ch);
    curl_close($ch);
    $result = json_decode($response, true);
    $category = $result["category"] ?? "unknown";

    // Apply CIPA filtering policy
    if (in_array($category, ["adult", "pornography", "gambling"])) {
        echo "BLOCKED: {$domain} ({$category})\n";
    } else {
        echo "ALLOWED: {$domain} ({$category})\n";
    }
}
?>