AWS GP3 volumes cost 20% less than GP2 with better baseline performance. Here's how to compare them, calculate your savings, and migrate without downtime.
AWS GP2 vs GP3: Save 20% on EBS with Better Performance (2026 Guide)
Quick Reference
| Price difference: | GP3 is 20% cheaper ($0.08 vs $0.10/GB-month) |
| Baseline IOPS: | GP3: 3,000 free / GP2: 3 per GB (often need to overprovision) |
| Migration: | No downtime, runs in background |
| Which to use: | GP3 for everything — no reason to use GP2 |
AWS GP3 volumes are cheaper and faster than GP2. Every GP2 volume in your account is costing you more than it should, and there’s no good reason to keep using them.
GP3 storage costs $0.08/GB-month versus GP2’s $0.10/GB-month. That’s a 20% savings before you even consider the performance advantages. GP3 also gives you independent control over IOPS and throughput, so you’re not forced to overprovision storage just to get the performance you need.
This guide covers the differences between GP2 and GP3, how to calculate your actual savings, and how to migrate your volumes without downtime.
GP2 vs GP3: Quick Comparison
| Feature | GP2 | GP3 |
|---|---|---|
| Storage Cost | $0.10/GB-month | $0.08/GB-month |
| Baseline IOPS | 3 IOPS per GB (min 100) | 3,000 IOPS (free) |
| Max IOPS | 16,000 | 16,000 (up to 80,000 with io2 Express) |
| Baseline Throughput | 128-250 MB/s (scales with size) | 125 MB/s (free) |
| Max Throughput | 250 MB/s | 1,000 MB/s |
| IOPS/Throughput Provisioning | Tied to volume size | Independent |
| Volume Size | 1 GB – 16 TB | 1 GB – 16 TB |
| Durability | 99.8-99.9% | 99.8-99.9% |
| Latency | Single-digit ms | Single-digit ms |
Bottom line: GP3 matches or exceeds GP2 performance at a lower price. There’s no technical reason to use GP2 for new volumes.
Why GP2 Costs More Than It Should
The fundamental problem with GP2 is that IOPS scales with volume size. You get 3 IOPS per GB, up to 16,000 IOPS at 5.3 TB.
This creates a perverse incentive: if you need more IOPS, you have to buy more storage, even if you don’t need it.
Example: You need 9,000 IOPS but only 500 GB of storage.
With GP2, you’d need a 3,000 GB volume (3 TB) to get 9,000 IOPS. You’re paying for 2.5 TB of storage you don’t need, just to hit your performance target.
With GP3, you provision exactly 500 GB of storage and add 6,000 IOPS on top of the 3,000 baseline. You pay for what you use.
GP3 Pricing Breakdown
GP3 has three cost components:
| Component | Price | Baseline (Free) |
|---|---|---|
| Storage | $0.08/GB-month | |
| IOPS | $0.005/IOPS-month | First 3,000 IOPS |
| Throughput | $0.04/MB/s-month | First 125 MB/s |
The baseline performance (3,000 IOPS, 125 MB/s) is included at no extra cost. You only pay extra if you provision beyond the baseline.
Real Savings Calculation
Let’s compare costs for a volume that needs 2 TB storage and 9,000 IOPS.
GP2 Cost
To get 9,000 IOPS with GP2, you need 3 TB of storage (9,000 ÷ 3 IOPS/GB = 3,000 GB):
- 3,000 GB × $0.10 = $300/month
GP3 Cost
With GP3, you provision exactly what you need:
| Component | Calculation | Cost |
|---|---|---|
| Storage | 2,000 GB × $0.08 | $160 |
| IOPS | 6,000 additional × $0.005 | $30 |
| Throughput | 125 MB/s (baseline, free) | $0 |
| Total | $190/month |
Savings: $110/month (37%)
If you want to maximize GP3’s throughput advantage (1,000 MB/s vs GP2’s 250 MB/s), add the extra throughput:
- Extra throughput: 875 MB/s × $0.04 = $35/month
- Total with max throughput: $225/month (still 25% less than GP2)
Is GP3 Always Cheaper?
Yes. We ran the numbers across all possible volume configurations.
For small volumes (under 1 TB), GP3 saves 20% purely on storage costs. For larger volumes where you need to overprovision GP2 for IOPS, savings can reach 35-40%.
There’s no volume size or performance level where GP2 is cheaper than GP3 with equivalent capabilities.
When to Use Each Volume Type
Use GP3 for:
- All new general-purpose workloads
- Boot volumes
- Development and test environments
- Medium-sized databases (under 64,000 IOPS)
- Any workload currently on GP2
Keep GP2 only if:
- You have a specific compliance requirement (rare)
- Your automation tooling can’t be updated (fix this)
There’s no technical reason to choose GP2 over GP3 for new deployments. Thankfully AWS have finally made GP3 the default option – but you may still have many instances with the old default of GP2.
GP2 to GP3 is just the start
If you have GP2 volumes, you probably have other EBS waste too — unattached volumes, old snapshots, over-provisioned IOPS. Our checklist covers all 32 highest-impact AWS optimizations.
See the Full Checklist →How to Migrate GP2 to GP3
Migration is straightforward and requires no downtime. AWS modifies volumes in place.
Using AWS Console
- Go to EC2 → Elastic Block Store → Volumes
- Select the GP2 volume
- Click Actions → Modify Volume
- Change Volume Type to gp3
- Set IOPS and Throughput (AWS auto-calculates equivalent values)
- Click Modify
The modification happens in the background. Volume performance is maintained during the transition.
Using AWS CLI
aws ec2 modify-volume \
--volume-id vol-1234567890abcdef0 \
--volume-type gp3
AWS automatically provisions IOPS and throughput to match your GP2 volume’s performance.
To specify custom values:
aws ec2 modify-volume \
--volume-id vol-1234567890abcdef0 \
--volume-type gp3 \
--iops 6000 \
--throughput 500
Migration Timing
- Small volumes: Minutes
- Large volumes: Up to several hours
- Performance: Maintained during transition
- Downtime: None
Monitor progress via:
- Console: Volume state shows “optimizing”
- CLI:
aws ec2 describe-volumes-modifications
Right-Size Before Migrating
Before converting GP2 to GP3, check if your GP2 volumes are oversized.
Remember: many GP2 volumes were made larger than necessary just to get more IOPS. With GP3, you don’t need that extra capacity.
Check your actual storage usage:
aws cloudwatch get-metric-statistics \
--namespace AWS/EBS \
--metric-name VolumeReadBytes \
--dimensions Name=VolumeId,Value=vol-1234567890abcdef0 \
--start-time 2025-12-01T00:00:00Z \
--end-time 2025-12-31T00:00:00Z \
--period 86400 \
--statistics Average
If your volume is significantly underutilized, shrink it before (or after) migrating to GP3 for maximum savings.
Common Questions
Does GP3 have latency issues?
No. GP3 had some early performance concerns when it launched in 2020. Those are long resolved. Current GP3 volumes have identical latency characteristics to GP2, single-digit milliseconds.
Can I rollback from GP3 to GP2?
Yes. Volume type changes are reversible using the same modification process. However, there’s rarely a reason to go back.
Do I need to stop my instance?
No. EBS volume modifications happen online with no downtime. Your instance continues running normally.
What about boot volumes?
GP3 works perfectly for boot volumes. AWS recommends GP3 for all general-purpose workloads including OS disks.
Will my IOPS stay the same after migration?
Yes. AWS automatically provisions GP3 IOPS to match your GP2 volume’s baseline. For a 500 GB GP2 volume (1,500 baseline IOPS), the GP3 conversion gives you 3,000 IOPS; actually more than you had before.
How long does migration take?
Most volumes complete within minutes to a few hours depending on size. You can continue using the volume normally during the process.
Are there any edge cases where GP2 is better?
Not anymore. GP3 matches or exceeds GP2 on every dimension: cost, IOPS, throughput, latency. The only reason to keep GP2 is if you have automation that hasn’t been updated yet.
Migrate at Scale with CloudFix
Migrating one volume is easy. Migrating hundreds across multiple accounts is tedious and error-prone.
CloudFix continuously scans your AWS accounts for GP2 volumes and calculates your potential savings. When it finds an opportunity, you review the recommendation and execute the migration with one click.
CloudFix handles:
- Discovery across all accounts and regions
- Savings calculation for each volume
- Safe migration via AWS Change Manager
- Audit trail via CloudTrail
- Ongoing monitoring for new GP2 volumes
No scripts to write. No volumes missed. No manual tracking.
Get a free savings assessment to see how much you’re currently overspending on EBS storage.
Related Resources:
How many GP2 volumes are you still paying for?
CloudFix scans every volume across all your accounts and calculates exact savings. One-click migration. No downtime. Free assessment shows your total.
