Billing — Sandchest

Sandchest is prepaid. You buy credits in US dollars, and transcription draws them down by the second of audio it actually completed. No seats, no subscription, no monthly minimum. This page covers how metering works, how to add credits, and where to see what you have spent.

Prepaid credits#

Your workspace holds a US-dollar credit balance. Every completed transcript subtracts the cost of its measured audio duration. When the balance runs out, new transcription requests are refused:

402 Payment Required

{ "error": "Your credit balance is exhausted. Add credits to continue transcribing." }

Existing transcripts keep processing — only new requests are held back. Add credits and everything resumes at once.

The dashboard shows your current price per audio hour, formatted like $0.21 / audio hour, alongside your balance.

What gets metered#


Unit	One second of audio
Measured from	The decoded media duration, not the file size or the wall-clock time
Charged when	The transcript reaches `status: "completed"`
Not charged	Anything that ends in `status: "error"`
Not charged	Uploads, polling, listing, deletion, captions, sentences, paragraphs, word search

Only the audio that finished counts. A transcript that fails during inference — an unsupported language, undecodable media, a worker fault — costs nothing. Storage, API calls and every derived resource are free; you pay for transcription.

audio_start_from and audio_end_at trim what is transcribed, and therefore what is billed.

Adding credits#

Go to sandchest.com/dashboard/billing and choose an amount.


Minimum	$5
Maximum	$1,000
Increments	Whole dollars only

Anything outside that returns Choose a whole-dollar credit amount between $5 and $1,000. Credits do not expire and are not refundable to a card; they stay on the workspace.

Only a workspace owner can buy credits or change billing settings. Admins can manage API keys and members; members can transcribe. See Authentication.

Automatic top-ups#

Turn on auto top-up and Sandchest buys more credits before you run dry.

Setting	Rules
Threshold	A whole number of dollars, at least `$1` and below the top-up amount
Amount	The same $5–$1,000 whole-dollar range as a manual top-up
Monthly limit	Between 1 and 100 top-ups per month — a hard ceiling on spend

Two prerequisites, each with its own message if you skip it:

A saved payment method — Add a payment method before enabling automatic top-ups.
At least one completed manual purchase — Purchase credits once before enabling automatic top-ups.

Turning auto top-up off never depends on any of that. Disabling it keeps your stored settings and simply stops future charges, so you can always stop spending.

Watching usage#

sandchest.com/dashboard/usage shows audio hours transcribed and what they cost. The billing page shows your remaining balance, plus anything already used but not yet reconciled with the payment provider — so the number you see is what you can actually still spend, not an optimistic one.

Per transcript, audio_duration is the billable length in seconds:

shell

curl -sS "https://stt-api.sandchest.com/v2/transcript?limit=100&status=completed" \
  -H "Authorization: $SANDCHEST_API_KEY" | jq '.transcripts | length'

Self-hosting#

There is no billing when you run Sandchest yourself. Set SANDCHEST_SELF_HOSTED=true and the entitlement check is bypassed entirely — no credits, no metering, no payment provider. Your costs are your own GPU, storage and bandwidth. See Self-hosting.

Verify#

Confirm your workspace can transcribe by creating a transcript. A 402 means you are out of credits; anything else means billing is not what is blocking you.

shell

curl -sS -o /dev/null -w '%{http_code}\n' https://stt-api.sandchest.com/v2/transcript \
  -H "Authorization: $SANDCHEST_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"audio_url":"'"$UPLOAD_URL"'"}'

expected output

Next#

Self-hosting — run the whole thing on your own hardware.