8 min readPublished 22 April 2025
Finding the right car battery can be confusing with so many types, sizes, and specifications. Knowing what to check and where to find the information makes the process much easier.
This guide explains how to determine what car battery you need, including where to find specifications, what to look for, and how to use our tools to find the perfect match.
Quick Answer
To find what car battery you need, check your vehicle's battery specification in the owner's manual, look at your existing battery label, or use our Battery Fitment Tool with your registration number. You need to match battery type (AGM/EFB/standard), size code, capacity (Ah), and CCA rating.
Common causes
- -Vehicle specifications determine required battery type and size
- -Start/Stop systems require AGM or EFB batteries
- -Battery size codes ensure physical fitment
Typical fixes
- -Check vehicle owner's manual for battery specification
- -Use Battery Fitment Tool with registration number
- -Match existing battery if replacing like-for-like
Finding Your Battery Requirements
Need to replace battery
Likely cause: Check existing battery or vehicle spec
Next step: Use Battery Fitment Tool or check manual
Vehicle has Start/Stop
Likely cause: Needs AGM or EFB battery
Next step: Check vehicle spec for exact type required
Don't know battery size
Likely cause: Check existing battery label
Next step: Look for size code (096, 027, etc.) on battery
What Do You Need to Check?
Several key specifications determine which battery your car needs. Understanding these helps you find the right replacement.
- Battery type: AGM, EFB, or standard flooded
- Size code: 096, 027, 075, etc.
- Capacity: Measured in Ah (Amp hours)
- CCA: Cold Cranking Amps rating
- Terminal layout: Positive/negative position
- Physical dimensions: Length, width, height
Where to Find Battery Specifications
Battery specifications can be found in several places. Use the method that's most convenient for you.
Use Our Battery Fitment Tool
The easiest way to find your battery requirements is using our Battery Fitment Tool. Enter your vehicle registration number for automatic lookup, or select your vehicle make, model, and year manually.
- Enter registration number for instant lookup
- Or select make, model, and year manually
- Shows exact battery type, size, and specifications
- Displays compatible batteries with prices
- Most accurate and convenient method
See also: Use Battery Fitment Tool
Check Vehicle Owner's Manual
Your vehicle's owner's manual contains battery specifications in the maintenance or technical specifications section.
- Look for 'Battery' or 'Electrical' section
- Shows battery type, capacity, and CCA
- May include size code or dimensions
- Check both printed and digital versions
Check Your Existing Battery
If your battery is still fitted, check the label for all specifications. This is the most reliable method if the battery is original equipment.
- Look for battery label on top or side
- Shows type (AGM/EFB/Standard), size code, capacity, CCA
- Note terminal layout (positive/negative position)
- Measure dimensions if label is missing
Determining Battery Type
Battery type (AGM, EFB, or standard) is crucial for compatibility, especially with Start/Stop systems.
- Start/Stop vehicles need AGM or EFB (check which)
- Non-Start/Stop vehicles can use standard flooded
- Advanced Start/Stop with regenerative braking requires AGM
- Basic Start/Stop can use EFB or AGM
- Never downgrade from AGM to standard
Find batteries by type
Search for batteries by technology type. Always verify exact fitment and specifications with your vehicle handbook before purchasing.
AGM batteries
Browse AGM batteries for Start/Stop systems and modern vehicles.
EFB batteries
EFB batteries for basic Start/Stop and standard vehicles.
Standard batteries
Traditional flooded batteries for older vehicles.
As an Amazon Associate, BatteryScout may earn from qualifying purchases made through the links above. This does not affect the price you pay.
Finding Battery Size
Battery size codes ensure the battery fits physically in your vehicle's battery tray.
- Size codes: 096, 027, 075, 110, etc.
- Also called Group numbers or EN codes
- Determines physical dimensions
- Must match exactly for proper fitment
- Check existing battery or use Fitment Tool
Capacity and CCA Ratings
Capacity (Ah) and CCA (Cold Cranking Amps) ratings affect battery performance and must match or exceed original specifications.
- Capacity (Ah): Energy storage, match or exceed original
- CCA: Starting power, match or exceed original
- Higher ratings provide more headroom
- Lower ratings may cause starting problems
- Check original specification for minimum requirements
See also: View complete CCA Chart
Common Mistakes to Avoid
Avoiding common mistakes ensures you get the right battery and avoid problems.
- Don't guess battery type - check vehicle specification
- Don't choose wrong size - it won't fit properly
- Don't downgrade from AGM to standard for Start/Stop
- Don't ignore capacity and CCA requirements
- Always verify specifications before purchasing
AI-Friendly Summary
- Use our Battery Fitment Tool with your registration number for easiest lookup
- Check vehicle owner's manual or existing battery label for specifications
- Match battery type (AGM/EFB/standard), size code, capacity, and CCA
- Start/Stop vehicles require AGM or EFB - check which type your vehicle needs
- Always verify specifications before purchasing to avoid compatibility issues
Frequently Asked Questions
How do I know what car battery I need?
Check your vehicle's battery specification in the owner's manual, look at your existing battery label, or use our Battery Fitment Tool with your registration number. You need to match battery type (AGM/EFB/standard), size code, capacity (Ah), and CCA rating.
Can I use our Battery Fitment Tool to find my battery?
Yes, our Battery Fitment Tool is the easiest way to find the right battery. Enter your vehicle registration number for automatic lookup, or select your vehicle make, model, and year manually. The tool identifies battery type, size code, capacity, CCA, and technology requirements.
What if I don't know my battery specifications?
If you don't know your battery specifications, use our Battery Fitment Tool with your vehicle registration or make/model details - it will identify exact requirements. Alternatively, check your vehicle handbook, consult a dealer, or measure your existing battery if still fitted.
Do I need AGM or EFB for my car?
If your vehicle has Start/Stop, you need AGM or EFB. Check your vehicle specification - basic Start/Stop can use EFB, while advanced Start/Stop with regenerative braking requires AGM. Use our Battery Fitment Tool to determine the exact type required.
What happens if I choose the wrong battery?
Choosing the wrong battery can cause starting problems, damage to the charging system, Start/Stop system failure, and premature battery failure. Always match battery type, size, capacity, and CCA to your vehicle's requirements.
