diff --git a/swh/model/model.py b/swh/model/model.py
--- a/swh/model/model.py
+++ b/swh/model/model.py
@@ -29,7 +29,7 @@
 
 from . import git_objects
 from .collections import ImmutableDict
-from .hashutil import DEFAULT_ALGORITHMS, MultiHash
+from .hashutil import DEFAULT_ALGORITHMS, MultiHash, hash_to_hex
 from .swhids import CoreSWHID
 from .swhids import ExtendedObjectType as SwhidExtendedObjectType
 from .swhids import ExtendedSWHID
@@ -58,6 +58,13 @@
 VT = TypeVar("VT")
 
 
+def hash_repr(h: bytes) -> str:
+    if h is None:
+        return "None"
+    else:
+        return f"hash_to_bytes('{hash_to_hex(h)}')"
+
+
 def freeze_optional_dict(
     d: Union[None, Dict[KT, VT], ImmutableDict[KT, VT]]  # type: ignore
 ) -> Optional[ImmutableDict[KT, VT]]:
@@ -491,7 +498,9 @@
             ["created", "ongoing", "full", "partial", "not_found", "failed"]
         ),
     )
-    snapshot = attr.ib(type=Optional[Sha1Git], validator=type_validator())
+    snapshot = attr.ib(
+        type=Optional[Sha1Git], validator=type_validator(), repr=hash_repr
+    )
     # Type is optional be to able to use it before adding it to the database model
     type = attr.ib(type=Optional[str], validator=type_validator(), default=None)
     metadata = attr.ib(
@@ -522,6 +531,9 @@
     SNAPSHOT = "snapshot"
     ALIAS = "alias"
 
+    def __repr__(self):
+        return f"TargetType.{self.name}"
+
 
 class ObjectType(Enum):
     """The type of content pointed to by a release. Usually a revision"""
@@ -532,6 +544,9 @@
     RELEASE = "release"
     SNAPSHOT = "snapshot"
 
+    def __repr__(self):
+        return f"ObjectType.{self.name}"
+
 
 @attr.s(frozen=True, slots=True)
 class SnapshotBranch(BaseModel):
@@ -539,7 +554,7 @@
 
     object_type: Final = "snapshot_branch"
 
-    target = attr.ib(type=bytes, validator=type_validator())
+    target = attr.ib(type=bytes, validator=type_validator(), repr=hash_repr)
     target_type = attr.ib(type=TargetType, validator=type_validator())
 
     @target.validator
@@ -566,7 +581,7 @@
         validator=type_validator(),
         converter=freeze_optional_dict,
     )
-    id = attr.ib(type=Sha1Git, validator=type_validator(), default=b"")
+    id = attr.ib(type=Sha1Git, validator=type_validator(), default=b"", repr=hash_repr)
 
     def compute_hash(self) -> bytes:
         git_object = git_objects.snapshot_git_object(self)
@@ -594,7 +609,7 @@
 
     name = attr.ib(type=bytes, validator=type_validator())
     message = attr.ib(type=Optional[bytes], validator=type_validator())
-    target = attr.ib(type=Optional[Sha1Git], validator=type_validator())
+    target = attr.ib(type=Optional[Sha1Git], validator=type_validator(), repr=hash_repr)
     target_type = attr.ib(type=ObjectType, validator=type_validator())
     synthetic = attr.ib(type=bool, validator=type_validator())
     author = attr.ib(type=Optional[Person], validator=type_validator(), default=None)
@@ -607,7 +622,7 @@
         converter=freeze_optional_dict,
         default=None,
     )
-    id = attr.ib(type=Sha1Git, validator=type_validator(), default=b"")
+    id = attr.ib(type=Sha1Git, validator=type_validator(), default=b"", repr=hash_repr)
 
     def compute_hash(self) -> bytes:
         git_object = git_objects.release_git_object(self)
@@ -656,6 +671,9 @@
     CVS = "cvs"
     BAZAAR = "bzr"
 
+    def __repr__(self):
+        return f"RevisionType.{self.name}"
+
 
 def tuplify_extra_headers(value: Iterable):
     return tuple((k, v) for k, v in value)
@@ -673,7 +691,7 @@
         type=Optional[TimestampWithTimezone], validator=type_validator()
     )
     type = attr.ib(type=RevisionType, validator=type_validator())
-    directory = attr.ib(type=Sha1Git, validator=type_validator())
+    directory = attr.ib(type=Sha1Git, validator=type_validator(), repr=hash_repr)
     synthetic = attr.ib(type=bool, validator=type_validator())
     metadata = attr.ib(
         type=Optional[ImmutableDict[str, object]],
@@ -682,7 +700,7 @@
         default=None,
     )
     parents = attr.ib(type=Tuple[Sha1Git, ...], validator=type_validator(), default=())
-    id = attr.ib(type=Sha1Git, validator=type_validator(), default=b"")
+    id = attr.ib(type=Sha1Git, validator=type_validator(), default=b"", repr=hash_repr)
     extra_headers = attr.ib(
         type=Tuple[Tuple[bytes, bytes], ...],
         validator=type_validator(),
@@ -750,8 +768,8 @@
 
     name = attr.ib(type=bytes, validator=type_validator())
     type = attr.ib(type=str, validator=attr.validators.in_(["file", "dir", "rev"]))
-    target = attr.ib(type=Sha1Git, validator=type_validator())
-    perms = attr.ib(type=int, validator=type_validator(), converter=int)
+    target = attr.ib(type=Sha1Git, validator=type_validator(), repr=hash_repr)
+    perms = attr.ib(type=int, validator=type_validator(), converter=int, repr=oct)
     """Usually one of the values of `swh.model.from_disk.DentryPerms`."""
 
 
@@ -760,7 +778,7 @@
     object_type: Final = "directory"
 
     entries = attr.ib(type=Tuple[DirectoryEntry, ...], validator=type_validator())
-    id = attr.ib(type=Sha1Git, validator=type_validator(), default=b"")
+    id = attr.ib(type=Sha1Git, validator=type_validator(), default=b"", repr=hash_repr)
 
     def compute_hash(self) -> bytes:
         git_object = git_objects.directory_git_object(self)
@@ -821,10 +839,10 @@
 class Content(BaseContent):
     object_type: Final = "content"
 
-    sha1 = attr.ib(type=bytes, validator=type_validator())
-    sha1_git = attr.ib(type=Sha1Git, validator=type_validator())
-    sha256 = attr.ib(type=bytes, validator=type_validator())
-    blake2s256 = attr.ib(type=bytes, validator=type_validator())
+    sha1 = attr.ib(type=bytes, validator=type_validator(), repr=hash_repr)
+    sha1_git = attr.ib(type=Sha1Git, validator=type_validator(), repr=hash_repr)
+    sha256 = attr.ib(type=bytes, validator=type_validator(), repr=hash_repr)
+    blake2s256 = attr.ib(type=bytes, validator=type_validator(), repr=hash_repr)
 
     length = attr.ib(type=int, validator=type_validator())
 
@@ -904,10 +922,14 @@
 class SkippedContent(BaseContent):
     object_type: Final = "skipped_content"
 
-    sha1 = attr.ib(type=Optional[bytes], validator=type_validator())
-    sha1_git = attr.ib(type=Optional[Sha1Git], validator=type_validator())
-    sha256 = attr.ib(type=Optional[bytes], validator=type_validator())
-    blake2s256 = attr.ib(type=Optional[bytes], validator=type_validator())
+    sha1 = attr.ib(type=Optional[bytes], validator=type_validator(), repr=hash_repr)
+    sha1_git = attr.ib(
+        type=Optional[Sha1Git], validator=type_validator(), repr=hash_repr
+    )
+    sha256 = attr.ib(type=Optional[bytes], validator=type_validator(), repr=hash_repr)
+    blake2s256 = attr.ib(
+        type=Optional[bytes], validator=type_validator(), repr=hash_repr
+    )
 
     length = attr.ib(type=Optional[int], validator=type_validator())
 
@@ -985,6 +1007,9 @@
     FORGE = "forge"
     REGISTRY = "registry"
 
+    def __repr__(self):
+        return f"MetadataAuthorityType.{self.name}"
+
 
 @attr.s(frozen=True, slots=True)
 class MetadataAuthority(BaseModel):
@@ -1090,7 +1115,7 @@
         type=Optional[CoreSWHID], default=None, validator=type_validator()
     )
 
-    id = attr.ib(type=Sha1Git, validator=type_validator(), default=b"")
+    id = attr.ib(type=Sha1Git, validator=type_validator(), default=b"", repr=hash_repr)
 
     def compute_hash(self) -> bytes:
         git_object = git_objects.raw_extrinsic_metadata_git_object(self)
@@ -1282,7 +1307,7 @@
     target = attr.ib(type=CoreSWHID, validator=type_validator())
     extid_version = attr.ib(type=int, validator=type_validator(), default=0)
 
-    id = attr.ib(type=Sha1Git, validator=type_validator(), default=b"")
+    id = attr.ib(type=Sha1Git, validator=type_validator(), default=b"", repr=hash_repr)
 
     @classmethod
     def from_dict(cls, d):
diff --git a/swh/model/swhids.py b/swh/model/swhids.py
--- a/swh/model/swhids.py
+++ b/swh/model/swhids.py
@@ -79,7 +79,7 @@
 _TSWHID = TypeVar("_TSWHID", bound="_BaseSWHID")
 
 
-@attr.s(frozen=True, kw_only=True)
+@attr.s(frozen=True, kw_only=True, repr=False)
 class _BaseSWHID(Generic[_TObjectType]):
     """Common base class for CoreSWHID, QualifiedSWHID, and ExtendedSWHID.
 
@@ -132,6 +132,9 @@
             ]
         )
 
+    def __repr__(self) -> str:
+        return f"{self.__class__.__name__}.from_string('{self}')"
+
     @classmethod
     def from_string(cls: Type[_TSWHID], s: str) -> _TSWHID:
         parts = _parse_swhid(s)
@@ -145,7 +148,7 @@
             ) from None
 
 
-@attr.s(frozen=True, kw_only=True)
+@attr.s(frozen=True, kw_only=True, repr=False)
 class CoreSWHID(_BaseSWHID[ObjectType]):
     """
     Dataclass holding the relevant info associated to a SoftWare Heritage
@@ -223,7 +226,7 @@
         return urllib.parse.unquote_to_bytes(path)
 
 
-@attr.s(frozen=True, kw_only=True)
+@attr.s(frozen=True, kw_only=True, repr=False)
 class QualifiedSWHID(_BaseSWHID[ObjectType]):
     """
     Dataclass holding the relevant info associated to a SoftWare Heritage
@@ -361,6 +364,9 @@
                 swhid += "%s%s=%s" % (SWHID_CTXT_SEP, k, v)
         return swhid
 
+    def __repr__(self) -> str:
+        return super().__repr__()
+
     @classmethod
     def from_string(cls, s: str) -> QualifiedSWHID:
         parts = _parse_swhid(s)
@@ -379,7 +385,7 @@
             ) from None
 
 
-@attr.s(frozen=True, kw_only=True)
+@attr.s(frozen=True, kw_only=True, repr=False)
 class ExtendedSWHID(_BaseSWHID[ExtendedObjectType]):
     """
     Dataclass holding the relevant info associated to a SoftWare Heritage
diff --git a/swh/model/tests/test_model.py b/swh/model/tests/test_model.py
--- a/swh/model/tests/test_model.py
+++ b/swh/model/tests/test_model.py
@@ -10,6 +10,7 @@
 
 import attr
 from attrs_strict import AttributeTypeError
+import dateutil
 from hypothesis import given
 from hypothesis.strategies import binary
 import pytest
@@ -18,6 +19,7 @@
 from swh.model.from_disk import DentryPerms
 from swh.model.hashutil import MultiHash, hash_to_bytes
 import swh.model.hypothesis_strategies as strategies
+import swh.model.model
 from swh.model.model import (
     BaseModel,
     Content,
@@ -40,6 +42,7 @@
     TimestampWithTimezone,
     type_validator,
 )
+import swh.model.swhids
 from swh.model.swhids import CoreSWHID, ExtendedSWHID, ObjectType
 from swh.model.tests.swh_model_data import TEST_OBJECTS
 from swh.model.tests.test_identifiers import (
@@ -75,6 +78,23 @@
     assert obj_as_dict == type(obj).from_dict(obj_as_dict).to_dict()
 
 
+@given(strategies.objects())
+def test_repr(objtype_and_obj):
+    """Checks every model object has a working repr(), and that it can be eval()uated
+    (so that printed objects can be copy-pasted to write test cases.)"""
+    (obj_type, obj) = objtype_and_obj
+
+    r = repr(obj)
+    env = {
+        "tzutc": lambda: datetime.timezone.utc,
+        "tzfile": dateutil.tz.tzfile,
+        "hash_to_bytes": hash_to_bytes,
+        **swh.model.swhids.__dict__,
+        **swh.model.model.__dict__,
+    }
+    assert eval(r, env) == obj
+
+
 @attr.s
 class Cls1:
     pass