Material Usage Tracking
Key Concepts
Printago records how much filament every print actually consumed: per color, per slot, per attempt. The numbers come from analyzing the sliced G-code itself, layer by layer, so a print that stopped partway is charged only for the layers it actually ran, and an object you skipped is charged only up to the layer it was skipped at. Each attempt keeps its own record alongside the slicer's original estimate, so you can always see predicted versus actual for any print, including the ones that didn't finish.
You'll see these numbers in the Material used section of the Print Telemetry panel, in the Material usage recorded notification, and in the print-history API. Each print also records what that filament cost. With the Filament Inventory add-on, the weight each print used also comes off that filament's stock, which stops at 0 g.
How usage is measured
When a job is sliced (or dispatched with an already-sliced file), Printago analyzes the G-code and builds a map of how much filament every layer uses, broken down by slot and, where the slicer marked them, by object. That map is what usage is measured against:
- A print that finishes is recorded at the slicer's own totals for the plate, per slot.
- A print that stops early, whether it failed or was cancelled, is charged only for the layers it completed. Printago takes the last layer the printer reported and sums the filament up to that point.
Totals are tracked in millimeters of filament and converted to grams using the density figures from the filament profile the plate was sliced with. If a profile doesn't supply a weight, that slot's usage is shown as a length instead of a weight.
Purge, prime tower, and flush filament is always counted in the totals. It isn't attributed to any particular object, because the printer extrudes it regardless of which objects end up printing.
Skipped objects
Skipping an object stops its filament from being counted from that point on. A skipped object is charged only up to the layer where it was skipped:
- Skipped at print start (excluded before the first layer): the object contributes nothing to the total.
- Skipped mid-print: the object is charged for the layers it printed before the skip, and nothing after.
This applies no matter where the skip came from. Objects skipped from Printago, from the printer's own screen, or from the Bambu app are all detected and accounted the same way.
Each attempt's print history record also stores how much filament the skipped objects would have used. So when a print's total comes in under the slicer's estimate, the record explains itself: the estimate assumed the whole plate, and the difference is sitting in the excluded amount.
Attributing filament to individual objects relies on the slicer labeling objects in the G-code, which OrcaSlicer and Bambu Studio do by default. If a skip can't be matched to an object in the G-code, Printago counts that filament as used rather than guessing at a deduction.
Cancelled prints
Cancelling a print from Printago records the filament used up to the layer the print reached, exactly as if the print had been stopped at the printer. Objects that had been skipped by that point are deducted the same way as on any other print.
A job cancelled before it ever started printing records no usage. If a print stopped but the printer never reported which layer it reached, Printago records the attempt with its details marked unknown rather than inventing a number.
Per-slot and per-color breakdown
Usage is recorded against the physical slot the filament actually came from: a specific AMS slot or the external spool. At the end of the print, Printago also snapshots which material was loaded in each of those slots, so the record stays accurate even if you later swap spools or reassign materials. That's what lets the Material used section show "Bone White · Bambu Lab PLA Matte, 12.4 g, AMS A Slot 2" long after the spool has moved on.
Filament cost
When a print ends, Printago works out what each slot's filament cost and keeps it on the print: the grams the slot used, multiplied by the price per kilogram of the filament it used. The Material used table on the job shows the price, where it came from, and the cost for each slot, with the total beneath.
The price is the most specific one Printago has for that filament, in this order:
- Spool price: the tracked spool's own price, as it was when the print drew from it. This needs the spool-tracking add-on; without it a slot is costed as its color.
- Delivery price: when the spool has no price of its own, the price on the delivery it arrived on.
- Color price: the color's own price, when it has one.
- Material price: the material's price.
The cost is written once and never changed. Editing a material's, a color's, or a spool's price afterwards changes what the next print costs and leaves every earlier print as it was. Retrying a job records a new cost for the new attempt, at the prices in effect then.
Failed and canceled prints are costed the same way, on the filament they used before they stopped.
Partial totals and prints with no cost
A slot whose filament has none of those prices reads no price. It has no cost, it is left out of the total, and the total is marked Partial with a line saying how many slots are missing. A slot loaded with only a material type and no color is the usual case. With the Filament Inventory add-on, anyone who can edit materials gets a Set a price link on that row. It opens the material's pricing; a price you set there applies from the next print on. The print you are looking at keeps what it recorded, though the Materials and Profit reports price its unpriced slots at the new price.
A dash in place of a cost means the cost is unknown, which is not the same as free:
- The print's weight could not be measured, so there are no grams to multiply. The table still shows the length used and the price.
- The print was made before Printago started recording filament cost. Those prints are not filled in afterwards.
Which spool a print used
The snapshot also names the physical roll. If the slot had a spool serial, whether the printer read it off the roll's RFID tag or it came from the tracked roll loaded in the slot, that serial is recorded on the attempt alongside the grams, per slot. A multi-material print records the right serial for each slot separately.
That turns the record around: instead of only asking "what did this print use", you can ask "which prints used this roll". Click a serial anywhere it appears (the Material used list or the Printer Materials dialog) to open its page: the spool's own page when a spool in your inventory carries it, or a page for the roll when none does, with every print off that roll, newest first, with the printer, slot, outcome and grams, and an Export CSV button.
A roll with no serial records nothing rather than a blank, so it can never be mistaken for a roll whose serial was lost. Because print history is never rewritten, prints finished before a roll's serial was known do not gain one.
What a print drew from stock
With the Filament Inventory add-on, the Material used table on a job has a Drawn from column saying what each slot took out of stock: Bulk, or a tracked spool named by its serial or label code. When the spool loaded in the slot has a serial the column doesn't already show, it sits underneath. When the stock held less than the print used, the column adds what it drew, for example "drew only 30 g", or "none in stock" when it was already empty. A slot that took nothing out of stock, such as one set to a material type with no color, shows a dash. Where it drew from links to its material's Spools tab on that color, opened on the spool when it was one (without spool tracking, to the material's Activity tab). A spool is named as it was when the print drew it, so renaming or deleting it later leaves the job as it was. Without the spool-tracking add-on, a slot that drew a spool says A roll, without naming or linking it.
On a phone, or where the job's panel is too narrow for the extra column, the same thing reads on a line under the material's name and its grams, next to the slot and the spool serial: "From bulk · AMS A Slot 1", "From A1B2C3D4 · drew only 30 g", or "Nothing drawn". When the stock it drew from was already empty, the line says "none in stock".
Retries and estimates
Every attempt gets its own usage record. Retrying a job never overwrites the previous attempt's numbers, so a failed run's partial usage sits next to the successful run's full usage.
Each history record also snapshots the slicer's estimate from the time of the print: estimated total weight, estimated per-filament usage, and estimated print time. Actual and estimated live on the same record, which is what makes usage useful for spotting drift between what the slicer predicts and what your printers really consume.
Where the numbers appear
- Print Telemetry panel: open any finished job from the Print Queue to see material used per color and slot, what each cost, the totals, and any skipped objects. See Print History & Telemetry.
- Notifications: the Material usage recorded event (under Settings > Notifications tab) fires when a print reaches any final state and includes the amount used, layers completed, and outcome. Webhook payloads additionally include the full per-slot breakdown and the excluded amount for skipped objects.
- Reports: the Materials and Profit reports add up each print's recorded filament cost.
- API: the
print-historyendpoints return every attempt with its actual usage, per-slot breakdown, filament cost (in total and per slot, with the price and where it came from), skipped objects, and the slicer estimate snapshot, and support filtering on the totals. See the developer docs.
With the Filament Inventory add-on, a finished print takes what it used out of the filament's bulk stock, or, with the spool-tracking add-on, out of the tracked spool loaded in its slot. Without Filament Inventory, recorded usage changes no remaining weight in Printago. Either way, the most-empty and most-full spool selection strategies use the remaining amount reported live by the printer (AMS/RFID), not Printago's records.