S3 Minimum-Duration Exit Planner

Estimate the remaining minimum-storage-duration component before a planned exit from S3 Standard-IA, One Zone-IA or Glacier Instant Retrieval. Supply confirmed storage-class entry times, object-version sizes and your applicable rates. The Actor returns per-object timing, modeled billable size, estimated remaining-duration exposure and an explicit list of records it cannot model.

This is an offline planning calculation, not an AWS bill, lifecycle simulator or deletion service. It needs no AWS credentials and never reads, changes or removes an object. Use it to prepare a review before an authorized cleanup or retention change, alongside AWS's own pricing and billing tools.

Key features

• Model 30-day minimums for Standard-IA and One Zone-IA and 90 days for Glacier Instant Retrieval.
• Apply the 128 KiB minimum billable size for those supported classes.
• Calculate with integer bytes, seconds and microdollars rather than floating-point money.
• Show the earliest timestamp at which each supplied class-duration minimum is satisfied.
• Keep unconfirmed entry times and missing rates unresolved.
• Reject conflicting stable object-version records; count exact duplicate export records once.
• Review up to 5,000 supplied plans within a bounded input and runtime.

Who should use it?

FinOps engineers, backup operators and platform teams planning repeated storage cleanup can use this Actor when they can establish storage-class transition history. It is especially useful for an approval workflow that needs machine-readable per-object estimates without giving an external process AWS account access.

Do not use it if the only timestamp you have is an unverified object creation or last-modified time. An object can enter a storage class later than it was created. The Actor deliberately requires confirmation rather than silently substituting a convenient date.

Practical use cases

Prepare a bounded set of cleanup candidates for a FinOps review. Identify IA objects whose planned exits precede the class minimum. Compare two planned exit times using the same verified rates. Show how small-object billing floors affect an estimate. Separate supported records from archival classes requiring a different metadata model before anyone treats a partial estimate as a portfolio total.

Quick start

Run the included invented example. A one-GiB object enters Standard-IA on October 1 and is planned to exit on October 11. With an illustrative rate of $0.03 per GiB-month and a 30-day model month, twenty days remain and the modeled amount is $0.020000.

The example rate is a calculation fixture, not a current AWS regional quote. Replace it with your applicable rate. Confirm the transition timestamp from authorized history, use stable pseudonymous object-version IDs and set a deliberate model month length. Review unresolved records before using the estimate.

Input example

{
  "billingMonthDays": 30,
  "ratesUsdPerGiBMonth": {"STANDARD_IA":"0.03"},
  "objects": [{
    "id":"VERSION-DEMO",
    "storageClass":"STANDARD_IA",
    "sizeBytes":"1073741824",
    "classEnteredAt":"2026-10-01T00:00:00Z",
    "classEntryConfirmed":true,
    "plannedExitAt":"2026-10-11T00:00:00Z"
  }]
}

Input parameters

Field	Meaning
billingMonthDays	Explicit denominator, integer 28–31
ratesUsdPerGiBMonth	Applicable rates for supported classes, decimal strings with at most six places
objects	1–5,000 object-version plans, total input at most 2 MB
id	Stable pseudonymous version identifier; do not include a private object path
storageClass	STANDARD_IA, ONEZONE_IA or GLACIER_IR for modeled records
sizeBytes	Nonnegative integer string, maximum 5 TiB
classEnteredAt	Confirmed UTC timestamp, or null when unavailable
classEntryConfirmed	Explicit boolean; false preserves an unresolved record
plannedExitAt	UTC timestamp at or after class entry

Timestamps must use exactly YYYY-MM-DDTHH:mm:ssZ. Rates are supplied by you and can be zero where genuinely applicable. Unknown fields are rejected. Unsupported storage classes can be listed, but remain unresolved; they are never assigned a guessed duration or rate. If no objects can be modeled, the run fails without a completed-plan event.

Output and verified example

The packaged example produces this verified summary:

{
  "uniqueObjects":1,
  "modeledObjects":1,
  "unresolvedObjects":0,
  "objectsBeforeMinimum":1,
  "ignoredExactDuplicates":0,
  "modeledRemainingDurationUsd":"0.020000"
}

Each modeled row includes size, modeled billable bytes, minimum days, remaining seconds, earliest minimum-satisfied timestamp, planned exit and the estimated amount. unresolved records the object reference and reason, such as unverified entry time or missing applicable rate. coverageComplete is false whenever unresolved records exist.

The default dataset contains one complete report, identical to the OUTPUT key-value record. Monetary outputs are six-decimal USD strings. checkedAt records processing time and does not imply AWS validated the proposed action.

How the model works

For a supported record, the Actor subtracts elapsed seconds from the class minimum and floors the remainder at zero. It uses the larger of supplied size and 131,072 bytes, multiplies by the supplied USD/GiB-month rate and the remaining fraction of the chosen model month. Each result is rounded half up to one microdollar before summing.

This explicit model is not AWS invoice rounding or a universal calendar-month forecast. Changing billingMonthDays changes the estimate. Customer discounts, rate tiers, credits and actual billing timing can also change real charges. The output therefore labels amounts as modeled remaining duration, never guaranteed fees or savings.

Exact repeated records with the same stable version ID are ignored with a count. Conflicting values for that ID fail, avoiding accidental double counting or arbitrary selection. Different versions require different stable IDs even if they share the same object key upstream.

Pricing

One completed bounded plan costs $0.32. A plan that clearly lists some unresolved objects is billable because it still contains a completed supported calculation. Invalid input or a plan with no modelable objects has no completed-plan event.

Ten completed reports cost $3.20 in Actor events, 100 cost $32 and 1,000 cost $320. There is no charge per flagged object. Apify platform usage and plan-specific conditions may apply separately. Inspect the run's current pricing and set a suitable spending limit. Repeated scenarios are separate reports and incur separate report events.

API integration and scheduling

import { ApifyClient } from 'apify-client';
import fs from 'node:fs';
const client = new ApifyClient({ token: process.env.APIFY_TOKEN });
const input = JSON.parse(fs.readFileSync('exit-plan.json', 'utf8'));
const run = await client.actor('wheresprada/s3-minimum-duration-exit-planner').call(input);
const { items } = await client.dataset(run.defaultDatasetId).listItems();
console.log(items[0].summary);

Your authorized export process must supply fresh plans and transition evidence. An Apify schedule with static input does not discover new AWS objects or rates. Review results before any separate deletion workflow. No automatic action is taken on a finding.

Limits and accuracy

The runtime budget is 128 MB and 30 seconds. Input is limited to 2 MB and 5,000 object-version records; oversized input fails rather than truncating. The calculation supports the three named classes only. Glacier Flexible Retrieval, Deep Archive, Intelligent-Tiering and their metadata or tier-specific models are excluded.

This does not estimate ordinary elapsed storage, request charges, retrieval costs, data transfer, taxes, discounts, total invoice changes or the operational value of retaining data. It does not interpret lifecycle filters, determine whether AWS would perform a transition, or establish whether an exit is permitted by retention or legal requirements. A satisfied minimum does not mean deletion is safe or that the total operation is free.

Privacy and security

No AWS keys, bucket names or object contents are needed. Use authorized metadata and stable pseudonyms. The Actor makes no AWS requests. Raw input and results remain in Apify storage under your account's access and retention settings; they may still reveal operational scale or timing. Restrict sharing and remove old planning records when they are no longer needed.

Troubleshooting and FAQ

Why is LastModified insufficient? It may not establish when the version entered its present storage class. Supply verified transition history or keep the record unresolved.

Why is a tiny object modeled as 128 KiB? The supported classes have a minimum billable object size. This differs from any separate lifecycle transition eligibility rule.

Can I use this for Deep Archive? No. Its archival metadata and duration model are intentionally unsupported rather than approximated silently.

Why does the estimate differ from my bill? Check rates, month denominator, version identity and omitted invoice components. The result is a narrow planning model.

Does zero remaining duration mean zero deletion cost? No. Other costs and obligations are outside this calculation.

Can the Actor delete objects after review? No. It has no AWS access and provides no destructive operation.

Support

Open an Apify Store issue with the run ID, expected arithmetic and a minimal pseudonymized fixture. Include the assumed rate unit and model month length. Do not provide AWS credentials, signed URLs or private object paths. A reproducible calculation lets support distinguish a defect from an unsupported billing scenario.