Key takeaways
- Amazon S3 shows total storage and object count in the Storage Lens default dashboard at no extra cost, and per bucket in the daily BucketSizeBytes metric in CloudWatch.
- BucketSizeBytes counts noncurrent versions and incomplete multipart uploads, so a versioned bucket can report far more than its live files; an inventory of current versions gives the live figure.
- Archived objects in Glacier Flexible Retrieval, Glacier Deep Archive and the Intelligent-Tiering archive tiers must be restored before they can be copied, and aws s3 sync copies current versions only.
- You don't need to export anything to apply: have your size in GB, years of history and user count ready, and the data vendor anonymizes the records before any AI lab sees them.
01
What is Amazon S3 data, and why do AI labs and data vendors buy it?
The short answer
Amazon S3 data is the collection of files that a company's software and staff store in Amazon S3, Amazon's file storage service: documents, photos, call recordings, logs and exports from other systems, often going back years. AI labs (companies that build and train AI models) and data vendors (companies that anonymize business records and package them for those labs) buy a copy because the files show the real content of the work, and when a file can be matched to a database record, such as a photo to a work order, the pair gives a model both the evidence and the known outcome.
What Amazon S3 stores
Amazon S3 (Simple Storage Service) is a file storage service run by Amazon Web Services (AWS). Files are called objects, and they are kept in buckets, which are named containers. An object's name, called its key, often works like a folder path, so a key such as inspections/2026/04/job-1042/roof.jpg says which job a photo belongs to.
Many other systems write into S3 without anyone noticing: a website saves uploaded photos there, a phone system saves call recordings, and a database saves its backups and exports. A bucket can therefore hold years of files from several programs side by side.
Why files tied to records teach an AI model something
An AI model learns by studying a very large number of examples and finding the patterns in them, and those examples are called training data. A photo alone shows only what a roof looks like. A photo whose key names a job, which a database record ties to a diagnosis and a repair, shows what the roof looked like and what the expert concluded about it.
AI labs now want to train AI agents, software that carries out a job step by step, and an agent learns a job from records of that job being done. Our guide AI training data: why AI companies want your company's data explains the mechanism.
How Amazon S3 fits into a dataset
An S3 bucket is usually one of several sources in a company's dataset, next to email, documents and tickets. Companies are paid $100K to $2M or more per dataset, according to micro1, the data vendor we typically refer companies to. The price covers the whole dataset, not each source on its own, and what your data is worth explains what moves it.
02
Where does Amazon S3 show how much data you have?
The short answer
Amazon S3 reports total storage and the number of objects for the whole account in two free places: the Account snapshot on the Buckets page, and the default dashboard of S3 Storage Lens, Amazon's storage analytics tool. For a single bucket, Amazon CloudWatch, the AWS monitoring service, publishes the same two figures daily as BucketSizeBytes and NumberOfObjects. Report total storage in gigabytes (GB).
How to read your total in the console
An AWS administrator (the person who manages the company's AWS account) does these steps. No paid tier is needed, but the person must have the right permissions. The dashboard steps follow Amazon's guide to viewing Storage Lens dashboards.
- Sign in with an IAM user or role (an AWS login that has been granted specific permissions) that may view S3 Storage Lens and read CloudWatch. The account's root user, the original login created with the AWS account, cannot open Storage Lens dashboards.
- In the S3 console's left navigation, go to Storage Lens > Dashboards and pick default-account-dashboard.
- On the Overview tab, the Snapshot section shows Total storage and Object count. The Buckets and Storage classes tabs break the totals down.
- To look at one bucket, open it and go to its Metrics tab, which charts daily storage under Bucket metrics. CloudWatch holds identical figures in its
AWS/S3namespace.
How to read one bucket from the command line
CloudWatch stores one size figure per bucket per storage class each day, so the command asks for one class at a time. This example reads a day of storage for the Standard class, and you repeat it for each other StorageType you use, such as StandardIAStorage or GlacierStorage:
aws cloudwatch get-metric-statistics --namespace AWS/S3 --metric-name BucketSizeBytes --dimensions Name=BucketName,Value=my-bucket Name=StorageType,Value=StandardStorage --start-time 2026-09-10T00:00:00Z --end-time 2026-09-11T00:00:00Z --period 86400 --statistics Average
Get object-level detail with an inventory report
An S3 Inventory report is a file listing every object in a bucket with the fields you ask for. Open the bucket's Management tab and select Create inventory configuration in the Inventory configurations area. Choose between Include all versions and Current versions only, then tick the fields Size, Last modified date and Storage class. The first report can take up to 48 hours to arrive.
What each figure counts
| Source | What it shows | Freshness and access |
|---|---|---|
| Storage Lens default dashboard | Total storage and object count for the account, by bucket and storage class | Updated daily; free metrics can be queried for 14 days; not visible to the root user |
CloudWatch BucketSizeBytes | One bucket's size per storage class | Reported once a day; needs CloudWatch read permission |
| S3 Inventory report | Every object, with size, last modified date and storage class | First report within 48 hours |
Why the number can be larger than the files you see
BucketSizeBytes adds up the size of every object and its metadata, both current and noncurrent versions, and the parts of any incomplete multipart uploads, according to Amazon's CloudWatch metrics reference. A bucket with versioning turned on, which keeps every earlier version of a changed or deleted file, can therefore report far more than the files you can see. The free Storage Lens metrics cover the account and its buckets, while paid advanced metrics go down to the prefix level and keep 15 months of history.
03
What should you know about your Amazon S3 data before you apply?
The short answer
Have three facts ready: the total storage in GB, how many years of files your buckets hold and how many people, devices or customers the files describe. Also note which storage classes the files sit in, because archived files take extra time to export. These go into the data manifest, the written summary of which sources hold your records, how many years each covers and roughly how much. You don't need to run an export to find them.
The size in GB
Report the total storage in GB, and check whether versioning is on. If it is, the metric includes old versions, so build an inventory report limited to Current versions only and add up its Size column to get the live figure.
The storage classes
Three groups of objects are archived and cannot be read or copied until they are restored: those in S3 Glacier Flexible Retrieval, those in S3 Glacier Deep Archive, and those in the Archive Access and Deep Archive Access tiers of S3 Intelligent-Tiering. Restoring adds time and cost to an export, so note how much of your data is in those classes. Objects in S3 Glacier Instant Retrieval need no restore.
The years of history
The oldest objects show up when you sort an inventory report by last modified date, and the bucket's creation date is an alternative starting point. Last modified is the later of an object's creation and its last change, so files that were rewritten look newer than they are.
The number of seats
For file storage, the seat count is the number of users, devices or customers whose files the buckets hold. The AWS logins that manage the buckets are not seats.
What you don't need to do first
Applying shares no data with anyone, and you don't need to export or clean anything first. The data vendor anonymizes records before any AI lab sees them, and nothing moves until a lawyer-reviewed license is signed. The application and each later step are laid out in how to sell your company's data.
04
How do you export your full Amazon S3 history?
The short answer
An AWS administrator lists each bucket with an S3 Inventory report, restores any archived objects, then copies the bucket with aws s3 sync to local disk or to another bucket. For very large or cross-account copies, an S3 Batch Operations Copy job uses the inventory as its list. A plain sync copies only the current version of each object, so version history needs a Batch Operations job.
Step 1: list what you will copy
Create an S3 Inventory report, as described above, for every bucket you intend to copy. The report is a checklist of how many objects there are, how large they are and where they are stored, and it can also be the manifest, the list of objects, that a Batch Operations job reads.
Step 2: restore archived objects
Amazon's guide to restoring archived objects covers both ways to do it. Only objects in the archived classes need this step.
- For a few objects, open the bucket in the S3 console, select the objects, choose Actions > Initiate restore, set how many days the restored copy stays available and pick a retrieval tier.
- For many objects, create an S3 Batch Operations job with the Restore operation, give it your inventory as the manifest and set the same number of days. One job handles either the Glacier classes or the Intelligent-Tiering archive tiers, not both, so restoring both kinds needs two jobs.
A restore from S3 Glacier Flexible Retrieval or S3 Glacier Deep Archive makes a temporary copy, so AWS bills both the archived original and the restored copy until the copy expires. Intelligent-Tiering restores at the Standard or Bulk tier have no retrieval charge and return the object to the Frequent Access tier.
Step 3: copy the bucket
The AWS command-line tool copies a whole bucket to local disk or to another bucket, and it copies only objects that are not there yet if you rerun it:
aws s3 sync s3://my-bucket /data/my-bucket aws s3 sync s3://my-bucket s3://destination-bucket
The tool skips Glacier objects and prints a warning. After their restores finish, run the same command again with --force-glacier-transfer added.
Step 4: use Batch Operations for very large or cross-account copies
- Start an S3 Batch Operations job that uses the Copy operation, with your inventory as the manifest, and create it in the destination Region, meaning the Region you are copying into.
- On a versioned bucket where order matters, copy the noncurrent versions in one job, wait for it to finish, then copy the current versions in a second job, because objects are not necessarily copied in manifest order.
- Compare the destination's object count and total size with the inventory report.
Amazon documents these limits for the Copy operation in its Batch Operations copy guide: objects up to 5 GB each, manifests of up to 20 billion objects, all source objects in one bucket and all destination objects in one bucket. If the destination bucket is unversioned, an object with the same key is overwritten. Use aws s3 sync for objects larger than 5 GB.
What the count and the copy include
The figures S3 reports and the files a sync copies are not the same set. The metric counts old versions and unfinished uploads, while a sync copies only the current version of each object and skips archived ones until they are restored.
Keep version history with Batch Operations
The aws s3 sync command takes only the latest version of every object. To keep the older versions too, build an inventory that lists all versions and have a Batch Operations job copy them.
How long an export takes
Amazon publishes no time for a copy, because it depends on the number and size of the objects, the Regions involved and any archived objects waiting for restore. The first inventory report alone can take up to 48 hours, so start that step early.
Sources: Amazon S3 User Guide, Viewing S3 Storage Lens metrics on the dashboards, CloudWatch metrics and dimensions, Restoring an archived object and Copy objects with Batch Operations. Steps checked against these pages in November 2026.
05
What stays private when Amazon S3 data is licensed?
The short answer
The company chooses which buckets and prefixes are copied, so a bucket holding backups, credentials or regulated records can be left out of the export altogether. The data vendor then replaces names and other identifying details with consistent stand-ins before an AI lab sees anything. The company keeps ownership of its files, and the license covers defined files for a defined use.
You choose what is in scope
A copy can be limited to the buckets and the prefixes (the folder-like beginnings of object keys) you name, and a bucket that is not copied never leaves your account. Because keys often carry customer names or job numbers, review them before you decide what is in scope. The data vendor deletes files too sensitive to clean safely instead of anonymizing them.
Names are replaced before a lab sees them
Anonymization means replacing every detail that identifies a person or a company, such as a name or an email address, with a stand-in that is the same every time it appears. Files raise a harder case than database fields, because faces in photos, voices in recordings and names printed inside documents are identifying details too. Our guide to how company data is anonymized for AI training explains how each kind is handled, what is deleted outright and how you review samples.
When files are matched to database records, such as inspection photos to work orders, the match is kept through the stand-ins. The photo still points to the same job, and the job no longer names the customer.
Ownership and payment
Licensing gives the buyer limited rights to a copy, while the company keeps ownership of the originals. Files you created are generally yours to license, but files that belong to customers or other companies may not be, and a lawyer's review settles that, as covered in whether it is legal to sell company data. The terms that matter, such as exclusivity, permitted use and deletion, are covered in data licensing. micro1 pays in full within 30 days of accepting the data, usually as a single payment.
Questions
Frequently asked questions
Why does BucketSizeBytes report more than the files in my bucket?
Because the metric counts more than the current files. It adds noncurrent object versions and the parts of incomplete multipart uploads, so in a versioned bucket the earlier versions can make up a big part of the total.
How often do the S3 storage numbers update?
Once a day. CloudWatch publishes the storage metrics daily and the Storage Lens dashboards refresh daily, but your first S3 Inventory report may need as long as 48 hours.
Can I copy objects that are in a Glacier storage class?
Only after restoring them, except in one class. Flexible Retrieval, Deep Archive and the Intelligent-Tiering archive tiers need a restore first, and S3 Glacier Instant Retrieval objects can be copied right away.
Is S3 Storage Lens free for checking my total storage?
Yes. Total storage and the object count are part of the free metrics on the default dashboard. Paying for advanced metrics buys detail down to the prefix and a longer look-back, 15 months against 14 days for the free ones.
Why can't I open Storage Lens when I'm signed in as the account owner?
Amazon does not let the account's root user view Storage Lens dashboards. Give a new or existing IAM user the Storage Lens permissions and sign in as that user.
Do I need to export Amazon S3 before I apply?
No. The application shares no data. You only need your total storage in GB, your years of history and your count of users or customers, and the Storage Lens dashboard gives you the first. The copy is needed later, after you sign the license.
What is Amazon S3 data worth to AI labs and data vendors?
Files are priced as part of a whole dataset rather than on their own. Companies are paid $100K to $2M or more per dataset, according to micro1, and the price depends on the years of history and how completely the records show each job. What your data is worth explains the factors.
Bottom line
Know what is in Amazon S3, then see what it is worth
You don't need to export anything to apply. Apply in two minutes, describe your records on the intro call, and micro1, the data vendor we typically refer companies to, prices the whole dataset and sends an offer 1–2 days later.
Not legal, tax or financial advice. Figures come from micro1's published pages and public reporting as of November 2026.