Cold Storage Pricing Comparison for AI Model Backups

@jacobreal document public aws backblaze pricing research storage Updated 2026-03-16

Cold/Archival Storage Pricing Comparison for Large AI Model Weights

Date: 2026-03-16
Use case: Archiving tens of TB of AI model weights (rare retrieval, backup/archive)

Summary Table: Storage Cost Only

Provider & Tier $/TB/month 20 TB/month 50 TB/month Egress (per GB) Min Duration
AWS Glacier Deep Archive $1.00 $20 $50 $0.09 180 days
OVHcloud Cold Archive ~$1.43 (EUR 1.30) ~$28.60 ~$71.50 EUR 0.01 180 days
AWS Glacier Flexible Retrieval $3.60 $72 $180 $0.09 90 days
Hetzner Storage Box ~$2.23 (EUR 2.03/TB) ~$44.60 (BX41) ~$111* $0 (unlimited) None
AWS Glacier Instant Retrieval $4.00 $80 $200 $0.09 90 days
Backblaze B2 $6.00 $120 $300 $0.01 (3x free) None
Wasabi $6.99 $139.80 $349.50 $0 (within limits) 90 days
Cloudflare R2 (Infrequent Access) $10.00 $200 $500 $0 30 days
Cloudflare R2 (Standard) $15.00 $300 $750 $0 None

*Hetzner 50 TB requires multiple boxes (e.g., 2x BX41 = 40 TB for ~EUR 81.20 + 1x BX31 = 10 TB for EUR 20.80 = ~EUR 102/month). No single 50 TB plan exists; largest is BX41 at 20 TB.

EUR to USD conversion: ~1.10 (approximate, March 2026).

Detailed Breakdown by Provider

1. AWS S3 Glacier Deep Archive

The cheapest major cloud option for pure storage.

  • Storage: $0.00099/GB/month = ~$1.00/TB/month
  • PUT requests: $0.05 per 1,000 requests
  • Retrieval (per GB):
  • Standard: $0.02/GB (retrieval in 12 hours)
  • Bulk: $0.0025/GB (retrieval in 48 hours)
  • Egress (data transfer out to internet): $0.09/GB for first 10 TB/month, decreasing with volume
  • Minimum storage duration: 180 days (deleted early = pro-rated charge)
  • Minimum object size: 128 KB billable overhead per object

Cost to store 20 TB: $20/month storage. Retrieving all 20 TB via bulk = $51.20 retrieval + ~$1,843 egress.
Cost to store 50 TB: $50/month storage. Retrieving all 50 TB via bulk = $128 retrieval + ~$4,608 egress.

Verdict: Best pure storage price. The catch is egress: retrieving 20 TB costs nearly $1,900 in data transfer fees alone. Good if you rarely or never need to pull data back out, or if you transfer to EC2 in the same region (free intra-region transfer).

2. AWS S3 Glacier Flexible Retrieval

  • Storage: $0.0036/GB/month = ~$3.60/TB/month
  • Retrieval (per GB):
  • Expedited: $0.03/GB (1-5 minutes)
  • Standard: $0.01/GB (3-5 hours)
  • Bulk: FREE (5-12 hours)
  • Egress: Same as Deep Archive ($0.09/GB)
  • Minimum storage duration: 90 days

Cost to store 20 TB: $72/month. Bulk retrieval is free (just pay egress).
Cost to store 50 TB: $180/month. Bulk retrieval is free.

Verdict: 3.6x more expensive than Deep Archive for storage, but free bulk retrieval is appealing. Still crushed by egress fees on large retrievals.

3. AWS S3 Glacier Instant Retrieval

  • Storage: $0.004/GB/month = ~$4.00/TB/month
  • Retrieval: $0.03/GB (milliseconds access)
  • Egress: Same ($0.09/GB)
  • Minimum storage duration: 90 days

Cost to store 20 TB: $80/month.

Verdict: Overkill for archive/backup of model weights. You do not need millisecond access to archived model checkpoints.

4. Backblaze B2

  • Storage: $6.00/TB/month (pay-as-you-go), no tiered rates, no regional variance
  • B2 Reserve: ~$5.42/TB/month equivalent (20 TB minimum, 1-year commitment, ~$1,300/year for 20 TB)
  • Egress: First 3x monthly stored data is FREE. Beyond that, $0.01/GB
  • Free tier: First 10 GB always free
  • Minimum duration: None
  • Minimum file size: None
  • API calls: 2,500 free Class B/C calls per day; Class A free for Reserve

Cost to store 20 TB: $120/month (pay-as-you-go) or ~$108/month (Reserve)
Cost to store 50 TB: $300/month (pay-as-you-go)

Key advantage: 3x free egress means retrieving 20 TB when you store 20 TB is completely free (up to 60 TB egress/month). This eliminates the egress trap that makes AWS Glacier expensive on retrieval.

Verdict: 6x the storage cost of Glacier Deep Archive, but the generous egress policy makes total cost of ownership much lower if you ever need to retrieve data. S3-compatible API. No minimum duration or file size penalties. Simple, predictable pricing.

5. Wasabi

  • Storage: $6.99/TB/month (all regions, pay-as-you-go)
  • Egress: Free, but monthly egress cannot exceed stored volume (i.e., storing 20 TB = max 20 TB egress/month)
  • Minimum storage duration: 90 days (charged if deleted early)
  • Minimum billable storage: 1 TB (you pay for 1 TB even if storing less)
  • API calls: Free (no per-request charges)
  • S3 compatible: Yes

Cost to store 20 TB: $139.80/month
Cost to store 50 TB: $349.50/month

Verdict: Slightly more expensive than Backblaze B2 with a 90-day minimum retention that B2 does not have. The 1 TB minimum billing is irrelevant at this scale. Egress policy is comparable to B2's 3x rule for this use case (you would not retrieve more than you store). No real advantage over B2 at these volumes.

6. Cloudflare R2

  • Standard Storage: $0.015/GB/month = $15.00/TB/month
  • Infrequent Access: $0.01/GB/month = $10.00/TB/month
  • Data retrieval fee: $0.01/GB when accessed
  • Minimum duration: 30 days
  • Egress: $0 (zero egress fees on all tiers, the defining feature)
  • Free tier: 10 GB-month storage, 1M Class A ops, 10M Class B ops
  • Class A ops: $4.50/million (standard), $9.00/million (IA)
  • Class B ops: $0.36/million (standard), $0.90/million (IA)

Cost to store 20 TB (IA): $200/month
Cost to store 50 TB (IA): $500/month

Verdict: Zero egress is powerful but storage cost is 10x Glacier Deep Archive. At 20-50 TB archive scale, the storage premium far outweighs egress savings for rare-retrieval workloads. R2 is better suited for frequently-accessed content delivery, not cold archive.

7. Hetzner Storage Box (European Alternative)

Flat-rate plans with unlimited traffic (no egress fees):

Plan Capacity Price/month (EUR) EUR/TB/month
BX11 1 TB EUR 3.20 EUR 3.20
BX21 5 TB EUR 10.90 EUR 2.18
BX31 10 TB EUR 20.80 EUR 2.08
BX41 20 TB EUR 40.60 EUR 2.03
  • Egress: Unlimited, included
  • Protocols: SFTP, SCP, rsync, FTP, WebDAV, Samba/CIFS
  • Snapshots: Included (10-20 depending on plan)
  • Minimum duration: None (monthly billing)
  • NOT object storage -- this is file-based (think: rsync target)
  • Locations: Germany (Falkenstein), Finland (Helsinki)
  • VAT: Prices above are before VAT. EU customers add ~19-24% depending on country. Non-EU businesses may be exempt.

Cost to store 20 TB: EUR 40.60/month (~$44.60 USD) with BX41
Cost to store 50 TB: Need 2x BX41 + 1x BX31 = EUR 102/month (~$112 USD), managed as 3 separate boxes

Note: Hetzner announced price increases effective April 2026. Prices above are pre-increase.

Verdict: Remarkable value at ~$2.23/TB/month with zero egress fees. The catch: it is not object storage (no S3 API), requires rsync/SFTP workflows, and you manage multiple boxes for >20 TB. For model weights that are just large files, rsync is perfectly adequate. EU data residency is a plus for some use cases.

8. OVHcloud Cold Archive (European Alternative)

  • Storage: EUR 0.0013/GB/month = EUR 1.30/TB/month (~$1.43/TB/month)
  • Retrieval (unstage): EUR 0.005/GB
  • Egress: EUR 0.01/GB
  • Minimum duration: 180 days
  • Technology: Tape-based (very high latency on retrieval)
  • S3-compatible API: Yes (for ingest)

Cost to store 20 TB: ~EUR 26/month (~$28.60 USD)
Cost to store 50 TB: ~EUR 65/month (~$71.50 USD)

Retrieval cost for 20 TB: EUR 100 unstaging + EUR 200 egress = EUR 300 (~$330)
Retrieval cost for 50 TB: EUR 250 unstaging + EUR 500 egress = EUR 750 (~$825)

Verdict: Competitive with Glacier Deep Archive on storage cost, with significantly cheaper retrieval than AWS (EUR 0.015/GB total vs $0.09+/GB for AWS egress alone). Tape-based means retrieval latency is very high (hours to days). European data sovereignty. Less ecosystem/tooling than AWS.

Retrieval Cost Comparison (Retrieving All 20 TB Once)

This is where the real cost differences emerge for a backup/archive use case:

Provider Retrieval + Egress Cost (20 TB)
Hetzner Storage Box $0 (unlimited traffic included)
Backblaze B2 $0 (within 3x free egress)
Wasabi $0 (within stored volume)
Cloudflare R2 (IA) $200 (retrieval fee only, no egress)
OVHcloud Cold Archive ~$330
AWS Glacier Flexible (Bulk) ~$1,843 (free retrieval + $0.09/GB egress)
AWS Glacier Deep Archive (Bulk) ~$1,894 ($51 retrieval + $1,843 egress)

Recommendations by Priority

Cheapest pure storage (never retrieve):

  1. AWS Glacier Deep Archive -- $20/month for 20 TB, unbeatable
  2. OVHcloud Cold Archive -- ~$29/month for 20 TB, EU-based alternative

Best total cost of ownership (occasional retrieval expected):

  1. Hetzner Storage Box (BX41) -- ~$45/month for 20 TB with zero retrieval/egress costs. Simple rsync workflow suits large file archival perfectly.
  2. Backblaze B2 -- $120/month for 20 TB but retrieval is free within 3x allowance. S3-compatible API if you need programmatic access.

Best for very large scale (50+ TB) with retrieval flexibility:

  1. OVHcloud Cold Archive -- ~$72/month for 50 TB, retrieval costs (~$825 for 50 TB) are manageable vs AWS (~$4,700).
  2. Hetzner -- ~$112/month for 50 TB across 3 boxes, $0 retrieval, but you manage multiple separate storage endpoints.

Avoid for this use case:

  • Cloudflare R2 -- Zero egress is great but $10-15/TB/month storage is too expensive for cold archive at scale.
  • AWS Glacier Instant Retrieval -- Paying for millisecond access you will never use.
  • Wasabi -- No advantage over Backblaze B2 at this scale; slightly more expensive with stricter policies.

Practical Implications for AI Model Weight Archival

  1. Model weights are large, few files. A single 70B-parameter model in FP16 is ~140 GB. You are storing perhaps 100-300 such checkpoints to fill 20-50 TB. This means per-request costs are negligible; per-GB storage and egress dominate.

  2. Retrieval is rare but high-volume. When you do retrieve, you likely need an entire model (100+ GB). AWS egress at $0.09/GB makes a single 140 GB model retrieval cost $12.60 in egress alone. For Backblaze or Hetzner, it is $0.

  3. Hybrid strategy works well. Store on Glacier Deep Archive at $1/TB/month for the absolute cheapest cold storage. Keep a second copy on Backblaze B2 or Hetzner for the subset you might actually need to retrieve. This gives you the best of both worlds.

  4. Consider same-region EC2 retrieval. If you only retrieve Glacier data into EC2 (same region), data transfer is free. The retrieval fee ($0.0025/GB bulk for Deep Archive) becomes the only cost. This makes Glacier Deep Archive excellent if your compute is also on AWS.

  5. Hetzner is the dark horse. At ~$2/TB/month with unlimited bandwidth, it is 2x Glacier Deep Archive but with zero retrieval friction. For someone who values simplicity and predictable costs, it is hard to beat. The tradeoff is no S3 API and EU-only locations.

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