Concepts

Currency settings

Choose how a workspace presents costs billed in different currencies, and read how a converted figure was produced.

Cloud providers invoice in the currency of the account, so one workspace can hold costs in several currencies at once. Every cost record keeps the currency it was billed in. What a workspace decides is how those costs are presented: in their own currencies, or converted into one.

Before you start

Open Settings, then Workspaces, and select the workspace. The Currency settings card holds the settings below. Each change is saved as soon as you make it; there is no save button.

A new workspace starts with conversion enabled, into its own currency, by monthly average.

Display preference

The currency costs fall back to where no billing currency applies: an empty date range, a new budget, an alert threshold. It never relabels a cost that was billed in another currency, because the billing currency is what the provider invoiced.

The display preference can be changed only while currency conversion is disabled. Once conversion is on, the conversion currency decides, the preference is greyed out, and the card says "The display preference is overridden by the currency conversion selection."

Currency conversion

Set Currency conversion to Enabled and choose the currency to convert into in the select beside it. Every cost figure in the workspace is then converted into it, and a converted total names the amount before conversion and the method.

With conversion Disabled:

A date range whose costs are all in one currency reads in that currency.
A date range that mixes currencies shows one total per currency and no combined total, because adding an amount in dollars to an amount in euros produces a number that means nothing. Cost reports and the Overview say "Costs in this range are billed in several currencies and are shown side by side", with a link to turn conversion on.
On the Overview, Cost trend draws one line per currency and names each in a legend. In Top services by cost each service is listed per currency, and its share is of the total in its own currency, under % of its currency. A cost report's breakdown measures each row's share the same way.
A budget counts only the costs already in its own currency and lists the rest after "Not counted:".

Exchange rate dates

Once conversion is enabled, Exchange rate dates chooses which published rates it uses. For the most accurate results, use the currency and the rate dates your provider bills you by.

Option	What it uses
Monthly average	The mean of the daily rates published across the charge's month. The current month moves a little with each publication until the month closes. Until the month's first ECB publication, spend in it converts at the last rate published before the month.
Transaction-date rate	The rate published for the charge's own day. A day the source does not publish, such as a weekend, uses the last published rate before it.

Where the rates come from

Costfluent converts with the European Central Bank's euro reference rates, published on business days at about 16:00 CET and loaded once a day after that. Rates are stored exactly as the ECB publishes them, as units of a currency per euro, and every other pair is derived through the euro. Costfluent does not accept customer-supplied exchange rates: a figure is only defensible if its source is one you can check yourself.

When no rate exists for a currency in the range you are looking at, such as a currency the ECB does not quote or a range older than the rates loaded, the amount is left out of the total and named beside it rather than added at a guess. The cost data of the Public API with the cost measure, and a CSV export of cost, keep that spend on rows of its own, in its billing currency and at its billed amount, rather than showing it as 0; a usage or count row still shows its cost as 0. The Public API's cost forecast names the current month's in unconverted.

With conversion enabled, each cost converts at the rate its exchange rate dates pick, through the euro; a cost with no rate is left out of the total and named beside it.

Reading a converted figure

A converted report carries a note under its total, for example:

$120.00 converted to €96.00. Converted to EUR at the mean of the ECB daily rates across the month. 1 EUR = 1.25 USD.

The second sentence names the method. The rate is added only when the whole range used one rate, for example a single closed month by monthly average; a range across several months or by transaction-date rate names no single rate.

The Exchange rates page

Open Settings, then Exchange rates. The page is for the workspace selected in the header.

The In force for this workspace card with the display preference, currency conversion, the currency converted into and the exchange rate dates — What is in force for the Production workspace.

In force for this workspace shows the display preference, whether conversion is on, the currency it converts into and the exchange rate dates, each with a sentence on what it does and a link to its section above, and a link to the workspace settings. If the workspace's settings cannot be read, the card says so and offers Retry.
Current market rate previews the latest published rate between any two currencies, with its source and the date it was published. Where no rate is loaded for the pair, it reads "No rate loaded for this pair"; where the rate cannot be read, it says so and offers Retry.
Exchange rate policy and Policy history follow; see below.

Exchange rate policy

Included in the Custom plan. Compare plans

On the Custom plan, an exchange rate policy can be recorded for a workspace. A policy names the method, the rate source and the period it applies to, and it overrides the workspace settings while it is in force, so a figure from a closed month keeps the method that produced it after the policy changes. When a date range spans a policy change, the conversion note in the console names the method of the range's latest month, and the API's description names each method with the months it converted. Policies are set by Costfluent with your finance team and are read-only in the console.

Policy history lists the current and earlier policies with their method, source, presentation currency and the dates they were in force: Effective from is the first day a policy applied and Effective to the last, or "Ongoing" while no later policy is set. On other plans the card reads "Exchange rate policy is not included", says that costs are presented by the workspace's currency settings, and offers Compare plans and Contact us. Where the plan includes policies but none is set yet, it reads "No exchange rate policy" and offers Contact us.

Public API

Workspace currency settings and the published rates are available through the Public API. See Authentication for tokens, and the API Reference for the full schemas.

Read a workspace's currency settings:

Code
curl -H "Authorization: Bearer $COSTFLUENT_API_TOKEN" \
  https://api.costfluent.com/v1/workspaces/wsp_example

Convert into euros by the monthly average (conversionMethod is monthlyAverage or transactionDate):

Code
curl -X PUT \
  -H "Authorization: Bearer $COSTFLUENT_API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"enableCurrencyConversion": true, "conversionCurrency": "EUR", "conversionMethod": "monthlyAverage"}' \
  https://api.costfluent.com/v1/workspaces/wsp_example

Pull the rates a report converted by:

Code
curl -H "Authorization: Bearer $COSTFLUENT_API_TOKEN" \
  "https://api.costfluent.com/v1/exchange-rates?startDate=2026-09-01&endDate=2026-09-30&targetCurrency=USD"

Cost data and cost summaries take an optional workspaceId, which decides whose currency settings present the figures. Without it, every figure stays in its billing currency:

Code
curl -H "Authorization: Bearer $COSTFLUENT_API_TOKEN" \
  "https://api.costfluent.com/v1/costs?workspaceId=wsp_example&startDate=2026-09-01&endDate=2026-09-30"

Access model Automatic syncing