Keel

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Use the Syringe Units converter

How many units is this volume?

Tools › Syringe Units: choose the direction, enter the volume or the units and your Syringe scale, and read the card; Your syringe draws the same amount on the barrel you pick.

AvailabilityFree · Pro only for: From Your Routine prefill

Written for Keel 1.0.0 · build 1Content 2026.09.14 · 2026.09.17-batch2Screens from build 1 (4cbadaa)

Where to start

Tools › Syringe Units — "Convert between milliliters and syringe units for your syringe scale." Free.

The screen

Under Your values: a direction switch and up to three fields; under Your syringe: a barrel picker and a drawing.

What appears when

There is no error copy: the result card needs the first field and a Syringe scale above zero; the drawing needs only a volume in mL → units mode, or the result in units → mL mode; Concentration never gates either.

Steps

  1. Choose mL → units or units → mL.
  2. Enter the first field: Volume (mL) or Units. No presets.
  3. Set Syringe scale in units/mL — it starts at 100; the chips 30, 50, 100 are shortcuts only if that scale is printed on your syringe.
  4. Optional: Concentration in mg/mL to see what the volume holds.
  5. Read the card: SYRINGE UNITS (a bare number) or VOLUME ("n mL"); with a concentration, That volume holds "n mg"; footer "Calculated from your values."
    Syringe Units screen in mL to units mode with Volume 0.35 mL, scale 100 units per mL, and a result card reading Syringe units 35.
    Fictional example: a volume and a syringe scale, and the units Keel computes from them — nothing here is a suggested amount.

    DisclosureFictional example. The values are the app’s own sample inputs, shown to explain how the fields relate; they are not a preparation or a recommendation.

    1. direction
    2. Volume
    3. Syringe scale
    4. SYRINGE UNITS
    Where this screen comes from
    File
    G4-F1-syringe-values-result.png (1320×1395); G4-F1-syringe-values-result.webp is a lossy encode of it
    Derivative SHA-256
    edd109cb2450794cf10a8e10d0f56955547857e206e7f85d348c87b6a49b94be
    Source
    G4-F1.png in package Keel-V1-4cbadaa-guide-figures-B-20260910-165828-62385
    Source SHA-256
    1ffc6b52acac71a7b33212d4d251cd17ea8c1e1b8117201c6bc2be6af4626a6a
    Package seal
    df48d7c70fb742b308677bf5d03a694f9122cc628b75451b9814645da1b37b52
    Captured from
    Keel 1.0.0 (1), implementation 4cbadaa1c63a0678b61e703583fadc9af226267d (reused-unchanged)
    Operation
    crop x0 y820 w1320 h1395 (source pixels, origin top-left)

    The numbered markers are drawn by the page, not into the image. Full provenance.

  6. Under Your syringe, pick 0.3 mL · 30 u, 0.5 mL · 50 u, 1 mL · 100 u (default), 3 mL or 5 mL; the callout at the fluid line reads "n u" on the insulin barrels and "n mL" on the others, and On this syringe repeats it.
    The Your syringe section with the 1 mL barrel selected, the drawn syringe about 35 percent full with a 35 u callout, and an On this syringe row reading 35 units.
    Fictional example: the same sample draw on a 1 mL syringe — the callout marks 35 u on the barrel and the reading row repeats it; nothing here is a suggested amount or syringe.

    DisclosureFictional example. The values are the app’s own sample inputs, shown to explain how the fields relate; they are not a preparation or a recommendation.

    1. barrel picker
    2. callout chip
    3. On this syringe
    Where this screen comes from
    File
    G4-F1b-syringe-drawing.png (1320×770); G4-F1b-syringe-drawing.webp is a lossy encode of it
    Derivative SHA-256
    7ecaf6105012bacdb56ea2bdc8cf3a03a930837a58c1f17a7288b9a63d2075dc
    Source
    G4-F1b.png in package Keel-V1-4cbadaa-guide-figures-B-20260910-165828-62385
    Source SHA-256
    050e99baf849011a52551efa3c39fd5609b67dfa4298a1ddb2d3cb051214699e
    Package seal
    df48d7c70fb742b308677bf5d03a694f9122cc628b75451b9814645da1b37b52
    Captured from
    Keel 1.0.0 (1), implementation 4cbadaa1c63a0678b61e703583fadc9af226267d (reused-unchanged)
    Operation
    crop x0 y1700 w1320 h770 (source pixels, origin top-left)

    The numbered markers are drawn by the page, not into the image. Full provenance.

What changes

Numbers show up to two decimals, never rounded to a mark. The card uses the scale you typed; the drawing and On this syringe use the barrel’s own scale (100 units per mL on the insulin barrels), so the two differ when your scale isn’t 100. A draw larger than the barrel fills the drawing, keeps the true number, and shows a warning; an exactly full barrel is not flagged.

Where: The result card and Your syringe

The Your syringe section with the 0.3 mL barrel selected, the barrel drawn full with a 30 u callout, the reading row still 35 units, and an orange warning that the draw is more than this syringe holds.
Fictional example: when the sample draw is larger than the chosen barrel, the drawing fills completely and Keel says so; the reading row keeps the true number — not a suggested amount or syringe.

DisclosureFictional example. The values are the app’s own sample inputs, shown to explain how the fields relate; they are not a preparation or a recommendation.

  1. barrel picker
  2. warning
Where this screen comes from
File
G4-F2-syringe-overflow.png (1320×840); G4-F2-syringe-overflow.webp is a lossy encode of it
Derivative SHA-256
29fc3bcd18058129b8c68b7832f2e34f37089a9e4cdceea2c9ec3b6e1a098034
Source
G4-F2.png in package Keel-V1-4cbadaa-guide-figures-B-20260910-165828-62385
Source SHA-256
d0c53fbe1a72b78ca9cdc80f8e3a61039aa2593a643f7cdafaf24253bc78a159
Package seal
df48d7c70fb742b308677bf5d03a694f9122cc628b75451b9814645da1b37b52
Captured from
Keel 1.0.0 (1), implementation 4cbadaa1c63a0678b61e703583fadc9af226267d (reused-unchanged)
Operation
crop x0 y1700 w1320 h840 (source pixels, origin top-left)

The numbered markers are drawn by the page, not into the image. Full provenance.

If it looks different

From Your Routine (Pro) opened it with Concentration prefilled?
Everything stays editable; see the From Your Routine guide.

Notes

  • No result card — Syringe scale is empty or zero, or the first field is empty (a first field of 0 still gives 0).
  • Type plain numbers with one separator; a number with exactly three digits after the separator and at most three before it (0.125) is read as a grouped whole number (125) — check the result matches what you meant.

This converter multiplies or divides the numbers you enter; nothing here suggests an amount, a syringe or a concentration.