There is no test for this. What veterinary hospice teams use instead is a structured look at the ordinary things: whether the pain is controlled, whether they eat and drink, whether they can keep themselves clean, whether they still take an interest, whether they can get up, and whether the good days still outnumber the bad. This page is that, written plainly, with a place to keep count.
The best-known version is the scale Dr. Alice Villalobos published in 2004 and revised in 2009, which scores each of those areas out of ten. It is copyrighted and we do not reproduce it. A 2022 review of every general quality-of-life tool for dogs and cats (Fulmer, Laven and Hill, open access) found that hers was built from veterinary experience with "minimal evidence of statistical validation", and that of the nine tools they looked at, none had been validated across every measure. That is not a criticism of the idea. It means the scoring is a way of making yourself look at each part of your animal's day in turn, not a number that decides anything.
Ohio State's veterinary hospital hands families a worksheet built on the same areas. Its own instruction matters more than the scoring: even one item on the wrong side, pain for instance, "may indicate a poor quality of life", and the thing to do with it is talk to your vet.
Write down the three to five things they love. Walks, the sound of the food bowl, the spot on the sofa, the greeting at the door, a particular game. Ohio State's advice is that when your pet is consistently unable to enjoy those things, it may be time to discuss euthanasia. It turns a fog into a short list you can check.
Mark each day good or bad. A face on a calendar is enough. Slow decline hides itself because you see the animal every day, and a run of marked days shows what memory smooths over. When the bad days start to outnumber the good, Ohio State says, it may be time.
Look at old photos and videos. Ohio State suggests this for exactly the same reason. The dog in the video from two summers ago is the comparison your eyes have lost.
Stays on this device. Nothing is sent to us or anyone. Print it and take it to the vet.
good mixed bad not marked
Three to five. Each week, mark whether they could still do it.
Ohio State's hospice program, from its own families: "Many families tell us that they waited too long; families rarely tell us they made the decision too soon." The same handout says that second-guessing afterwards "is normal and natural" and "does not mean you made the wrong choice", and that many animals allowed to die naturally do so overnight or while the owner is out.
The 2016 AAHA and IAAHPC end-of-life guidelines cite studies finding that 30% of owners experience significant grief after losing a pet and 50% question their decision after euthanasia. They also say plainly that both euthanasia and a hospice-supported natural death are medically and ethically acceptable, and that the vet's job is to support the owner's decision even where the vet's own values differ.
A 2017 paper in Frontiers in Veterinary Science (open access) puts the profession's side of it: vets themselves carry "the conundrum of ending an animal's life too soon, or waiting too long". We looked for a study that measures which way people more often regret, and did not find one. The "too long" line above is what a hospital says its families tell it, not a statistic.
This is the part people are most afraid to ask about, so here it is from the AVMA and Cornell's veterinary college, in their words where it matters.
Your vet may give a sedative first; the AVMA's euthanasia guidelines strongly encourage it, especially when the owner is in the room. Often a catheter is placed in a vein so the drug goes in cleanly. The euthanasia drug is usually a barbiturate, the same class used for anesthesia. The AVMA: after it is injected, "your pet will immediately become deeply and irreversibly unconscious as the drug stops brain function. Death is quick and painless." The ASPCA puts it at about 10 to 20 seconds, like going under for surgery.
Things you may see, none of which mean pain, because the animal is already unconscious. Cornell: "The eyes remain open in most cases." The last few breaths can be deep or gasping, which Cornell calls agonal, "involuntary muscle contractions"; the AVMA lists the same reflexes, legs or head moving and deep breaths, and says "these are reflexes and don't mean that your pet is in pain or is suffering." After death the muscles relax completely, often with urine or stool, which Cornell says "is completely normal". Occasional twitching afterwards is nerve chemistry, not life.
Whether you stay is yours to decide. The AVMA: some owners stay, some say goodbye beforehand, "this is a very personal decision." Cornell says the same. If you stay, ask the vet to tell you each step before it happens; the AAHA guidelines say that is how it should be done.
National averages from the 2025 CareCredit cost study, pages dated May and June 2026. For a dog: at the clinic $139 (range $110 to $253), at home $410 ($325 to $747), private cremation $260 ($206 to $473), pet cemetery burial $831. For a cat: $158 ($125 to $286), $359 ($284 to $653), $180 ($142 to $326), $566. Lap of Love, the largest in-home service, lists a base price of $530 to $535 in its Chicago and Philadelphia pages, with a $100 to $200 surcharge for evenings, weekends and holidays, aftercare extra. Communal cremation, where ashes are not returned, has no survey figure; PetMD says from about $50. The vet bill page has the rest.
Two university hotlines are staffed by veterinary students trained by grief counselors. Cornell's Pet Loss Support Hotline is 607-218-7457; its hours change by season, so call and listen to the message. Tufts' helpline is 508-839-7966, staffed 6 to 9 p.m. Eastern, Monday to Thursday, with voicemail the rest of the time and calls returned at the next shift. Cornell's page also lists the Chicago Veterinary Medical Association line at 630-325-1600. Lap of Love runs free weekly online groups and a line at 855-933-5683; it is a company and also sells paid sessions, so know which you are being offered.
Ohio State's handout has sections on how the decision affects children and the other animals in the house. Ask your vet about both; it is part of the conversation, not an afterthought.
The 50% who second-guess the decision are not wrong to have made it. The guidelines' own phrase for readiness is the one to keep: "as ready as you can be."
How to tell whether a dog is in pain, with a checklist to print for the vet: How do I know if my dog is in pain?
How to tell whether a cat is in pain, with the five things vets read in a cat's face: How do I know if my cat is in pain?