Conditional Monitoring

Set conditions to control when notifications are triggered based on content

Conditional Monitoring

Conditional Monitoring allows you to set rules that determine when notifications should be sent. Instead of getting alerted for every change, you can filter notifications based on specific conditions - like price thresholds, keyword presence, or numeric values.

What is Conditional Monitoring?

Conditional monitoring adds intelligent filtering to change detection. While change detection finds what changed, conditions determine whether to notify based on the changed content.

How it works

1. changedetection.io detects a change on the page
2. Conditions are evaluated against the new content
3. If conditions are met → Notification is sent ✅
4. If conditions are NOT met → Change is recorded, but no notification ❌

When to Use Conditions

Price Thresholds

Only notify when price drops below $50 or rises above$200

Keyword Filtering

Alert only when specific keywords appear or disappear

Numeric Ranges

Notify when stock count, ratings, or other numbers meet criteria

Text Presence

Trigger when specific text exists or is removed from the page

Setting Up Conditions

Accessing Condition Rules

1. Edit Watch

   Click Edit on any watch

2. Find Conditions Section

   Scroll to the “Conditions” section near the bottom

3. Choose Match Logic

   Select “Match all” (AND) or “Match any” (OR)

4. Add Condition Rules

   Configure field, operator, and value for each rule

Condition Components

Each condition rule has three parts:

1. Field (What to Check)

Select what content to evaluate:

Field	Description	Example Use Case
Text	The extracted page content	Check if “Out of Stock” appears
Number	Numeric value extracted from page	Check if price < 100
URL	The watch URL	Conditional logic based on URL

Extract specific values first

For best results, use Extract text filters to isolate the value you want to check:

1. Use filter: Price: (\d+\.\d+) to extract price
2. Then condition: Number < 50

2. Operator (How to Compare)

Available operators:

Text Operators

Operator	Description	Example
Contains	Text includes the value	Text contains “In Stock”
Does not contain	Text excludes the value	Text does not contain “Sold Out”
Matches regex	Text matches regular expression	Text matches ^Price: \$\d+
Equals	Text exactly matches value	Text equals “Available”
Does not equal	Text doesn’t match value	Text does not equal “Unavailable”

Numeric Operators

Operator	Description	Example
> (Greater than)	Number is larger than value	Number is greater than 100
< (Less than)	Number is smaller than value	Number is less than 50
>= (Greater or equal)	Number is at least value	Number is at least 10
<= (Less or equal)	Number is at most value	Number is at most 500
== (Equal)	Number exactly equals value	Number equals 0
!= (Not equal)	Number doesn’t equal value	Number does not equal -1

3. Value (What to Compare Against)

The value to compare the field against:

• For text: Enter the text/keyword/regex pattern
• For numbers: Enter the numeric value (integers or decimals)
• Case sensitivity: Text comparisons are case-insensitive by default

Match Logic

Control how multiple conditions are evaluated:

Match ALL (AND)

All conditions must be true to send notification

Example:

Rule 1: Text contains "In Stock"
Rule 2: Number < 100

Match: ALL

Result: Notifies only when BOTH in stock AND price < $100

Use for: Strict filtering where all criteria must be met

Match ANY (OR)

Any condition being true will send notification

Example:

Rule 1: Text contains "Sale"
Rule 2: Text contains "Discount"
Rule 3: Number < 50

Match: ANY

Result: Notifies if on sale, discounted, OR price < $50

Use for: Flexible filtering with multiple trigger conditions

Common Use Cases

Price Drop Alert (Below Threshold)

Goal: Only notify when price drops below $100

Configuration:

Conditions:
  Field: Number
  Operator: <
  Value: 100
  
Match: ALL

Setup:

1. Use “Extract text” filter: \$([0-9.]+) to extract price
2. Add condition: Number < 100
3. Save watch

Result: Notifications only when extracted price is less than $100

Price in Range (Between Two Values)

Goal: Notify when price is between $50 and$150

Configuration:

Conditions:
  Rule 1:
    Field: Number
    Operator: >
    Value: 50
    
  Rule 2:
    Field: Number
    Operator: <
    Value: 150
    
Match: ALL

Result: Notifies only when 50 < price < 150

Keyword Presence (Text Contains)

Goal: Alert when “Hiring” or “Now Accepting Applications” appears

Configuration:

Conditions:
  Rule 1:
    Field: Text
    Operator: Contains
    Value: Hiring
    
  Rule 2:
    Field: Text
    Operator: Contains  
    Value: Now Accepting Applications
    
Match: ANY

Result: Notifies if either phrase appears on the page

Stock Count Monitoring

Goal: Alert when stock count drops below 10 units

Configuration:

Setup:
  Extract text filter: Stock: (\d+) units
  
Conditions:
  Field: Number
  Operator: <
  Value: 10
  
Match: ALL

Result: Notifies when stock count < 10

Restock Alert (Keyword Disappears)

Goal: Notify when “Out of Stock” is removed from page

Configuration:

Conditions:
  Field: Text
  Operator: Does not contain
  Value: Out of Stock
  
Match: ALL

Result: Notifies when “Out of Stock” text is no longer present

Rating Threshold

Goal: Alert when product rating rises above 4.5 stars

Configuration:

Setup:
  Extract text filter: Rating: ([0-5]\.[0-9])
  
Conditions:
  Field: Number
  Operator: >
  Value: 4.5

Result: Notifies when rating > 4.5

Advanced Conditional Logic

Multiple Keyword Detection (ALL)

Scenario: Notify only when page contains BOTH “Premium” AND “Discount”

Rule 1: Text contains "Premium"
Rule 2: Text contains "Discount"

Match: ALL

Price Drop OR Keyword

Scenario: Alert if price < $50 OR “Sale” appears

Rule 1: Number < 50
Rule 2: Text contains "Sale"

Match: ANY

Complex Price Condition (Outside Range)

Scenario: Notify when price drops below $20 OR rises above$100 (alert on extremes)

Rule 1: Number < 20
Rule 2: Number > 100

Match: ANY

Regex Pattern Matching

Scenario: Alert when email address appears in specific format

Field: Text
Operator: Matches regex
Value: [a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}

Match: ALL

Combining with Other Features

Conditions + Restock Monitoring

Scenario: Monitor product, notify only when in stock AND price < $200

Setup:

1. Use “Restock & Price Detection” processor
2. Add conditions:
   Rule 1: Text contains "In Stock"
   Rule 2: Number < 200
   Match: ALL
   

Conditions + Browser Steps

Scenario: Login, navigate to account balance, alert if balance < $100

Setup:

1. Browser Steps: Login and navigate to balance page
2. Extract text: Balance: \$([0-9.]+)
3. Condition: Number < 100

Conditions + Visual Selector

Scenario: Select price element, notify only on price drop

Setup:

1. Visual Selector: Select price element
2. Extract text: \$([0-9.]+)
3. Store original price on first check
4. Condition: Number < [previous_price]

For price comparisons over time

Use the built-in Restock monitoring feature instead of manual conditions. It automatically tracks price changes and has built-in thresholds.

Best Practices

Extract before conditioning

Use Extract text filters to isolate the exact value before applying conditions.

Example:

• Page shows: “Price: $49.99 (was$79.99)”
• Extract filter: Price: \$([0-9.]+)
• Extracted: 49.99
• Condition: Number < 50 ✅

Without extraction, the condition would check the entire text.

Test conditions before deploying

After setting up conditions:

1. Click “Check now” to run the watch
2. View the extracted content in the Preview tab
3. Verify conditions would evaluate correctly
4. Adjust extract filters or condition values as needed

Use specific operators

Choose the most specific operator for your use case:

• “Contains” for flexible keyword matching
• “Equals” for exact text matching
• “Matches regex” for complex patterns
• Numeric operators for price/number comparisons

Keep conditions simple

Complex multi-rule conditions can be hard to debug.

Instead of:

10 rules with complex regex patterns

Try:

2-3 clear rules with simple comparisons
Create multiple watches if needed

Document your logic

Use watch titles to indicate conditions:

• “Product X - Alert when < $50”
• “Job Board - Notify on ‘Hiring’ keyword”
• “Stock - Alert when count < 10”

Troubleshooting

Condition Never Triggers

Value not being extracted

Problem: Condition checks the full page text, not the extracted value

Solution:

1. Add an “Extract text” filter to isolate the value
2. Test with “Check now” and view Preview tab
3. Verify the extracted value appears correctly

Wrong operator for data type

Problem: Using numeric operator on text, or vice versa

Solution:

• For prices/numbers: Use Field = Number and numeric operators (< > ==)
• For keywords/text: Use Field = Text and text operators (contains, equals)

Regex pattern incorrect

Problem: “Matches regex” condition doesn’t match

Solution:

• Test regex pattern in a regex tester (regex101.com)
• Check for escaping issues (use \\ for literal backslash)
• Verify the pattern matches the actual page content format

Match logic set incorrectly

Problem: Using “Match ALL” when you need “Match ANY” or vice versa

Solution:

• ALL: All rules must be true (strict)
• ANY: At least one rule must be true (flexible)

Verify which logic matches your intent.

Condition Always Triggers

Possible causes:

1. Condition too broad:

   • “Text contains ‘a’” will always match (most pages have the letter ‘a’)
   • Make conditions more specific

2. Number extraction failing:

   • If number can’t be extracted, default value (0 or empty) may match condition
   • Verify extraction is working

3. Multiple values extracted:

   • If extraction finds multiple numbers, condition may check the first one
   • Refine extraction regex to target exact value

Notifications Still Send Despite Conditions

Check:

1. Are conditions enabled?
   • Verify condition rules are configured and saved
2. Is there a separate trigger text filter?
   • “Trigger text” (different feature) may override conditions
   • Check if “Keyword triggers” field is set
3. Global vs watch notifications:
   • Check if global notifications are sending (they ignore per-watch conditions)
   • Configure conditions in both global and per-watch if needed

Condition Examples by Scenario

E-commerce Product Monitoring

Price Drop Below Budget

Extract: \$([0-9.]+)

Condition:
  Field: Number
  Operator: <
  Value: 50

Job Board Monitoring

Senior Position Posted

Condition:
  Rule 1: Text contains "Senior"
  Rule 2: Text contains "Engineer" 
  Match: ALL

Real Estate Listings

Price Drop

Extract: Price: \$([0-9,]+)

Condition:
  Field: Number
  Operator: <
  Value: 500000

Stock/Inventory Tracking

Low Stock Alert

Extract: In Stock: ([0-9]+)

Condition:
  Field: Number
  Operator: <
  Value: 10

Conditions vs. Other Features

Conditions vs. Trigger Text

Feature	Purpose	Example
Trigger Text	Wait for specific text to appear before detecting ANY change	Wait for “Pre-order Available” then start monitoring
Conditions	Filter notifications based on content criteria	Only notify when price < $50

Key difference: Trigger text delays monitoring start. Conditions filter notifications.

Conditions vs. Filters

Feature	Purpose
Filters (CSS/XPath/Extract)	Control what content is monitored
Conditions	Control when notifications are sent

Use together:

1. Filters extract the price: $49.99
2. Conditions decide whether to notify: if price < 50

Related Features

Filters & Extraction

Extract specific values to use in conditions

Restock Monitoring

Built-in price and stock conditions

Trigger Text

Wait for specific text before monitoring

Next Steps

1. Set Up Your First Condition

   Create a price threshold condition on a test watch

2. Combine with Extraction

   Use Extract text filters to isolate values for conditions

3. Test Multiple Rules

   Experiment with Match ALL vs Match ANY logic

4. Configure Notifications

   Set up alerts to receive when conditions are met